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Nanomaterials, nanostructures and nano-devices

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Nano-engineering of materials and interfaces: design, synthesis and applications

Introduction and scope:

Nanofabrication techniques play a key role in enabling the miniaturization of existing thin film devices, as well as fostering a plethora of new device concepts. Recent advances in diagnostic techniques and computational modeling allow to study and tune the properties of materials and interfaces at atomic-scale, encompassing the research fields of physics, chemistry and materials science. Materials with new functionalities can be designed and synthetized with atomically-scale precision, opening new frontiers in nanotechnology.

This symposium is a multi-disciplinary forum devoted to forefront advances in the research field of multifunctional nanomaterials and interfaces. Interfaces play an essential role in virtually all materials and devices, encompassing a broad variety of applications related to surface processes. The focus will be on the modeling of surface chemistry processes, synthesis and device integration of novel nanomaterials for application in flexible electronics, photovoltaics, solar energy harvesting and conversion, data and energy storage and gas sensing.

More specifically, the topics will include, but not be limited to:

  • Computational modeling of functional nanomaterials and interfaces, with particular attention to surface processes;
  • Advanced fabrication techniques of functional nanomaterials, including: thin films, nanotubes and nanowires, porous and hybrid nanomaterials;
  • Advanced characterization techniques;
  • Device integration of nanomaterials and investigation of their functional applications;
  • Safety and sustainability of nanomaterials and devices

Examples range from materials modeling, deposition of nanomaterials, metamaterials, organic-inorganic nano-assemblies, quantum well and superlattice structures, as well as upscaling and integration of nanomaterials in devices with improved performances and decreasing size. Besides involving the participation of worldwide recognized speakers, the symposium is devoted to young scientists and is expected to foster the creation of excellence EU networks in the field of applied material science, even in view of the upcoming H2020 calls. Ultimately, the symposium aims at promoting new directions in the synthesis of functionally tailored nanomaterials, through the concurrence of scientists from complementary expertise fields.

Hot topics to be covered by the symposium:

  • Computational techniques for nanomaterials and surface science
  • Atomic-scale engineering
  • Nanomaterials and nanodevices
  • CVD, (plasma enhanced) ALD, spatial ALD, atomic layer etching, molecular beam epitaxy, pulsed laser deposition
  • Solution based synthesis, hydrothermal processing, sol-gel routes, template-directed solution synthesis
  • Structural, compositional and morphological nanomaterial characterization by means of advanced techniques
  • Targeted applications: displays, EUV lithography, light management for photovoltaics, OLEDs, solar cells, photo-electrochemical water splitting, solar fuels, photo-catalytic processes for air and water disinfection, batteries, sensors

Tentative list of invited speakers:

  • Jan-Willem Maes, ASM International, Leuven, Belgium, ALD of nanomaterials: from lab to fab
  • Martyn McLachlan, Imperial College London, United Kingdom, Metal oxides grown by PLD, ALD, solution-phase and their application in hybrid solar cells Prof. Santiago Gomez Ruiz, Universidad Rey Juan Carlos, Spain Application of metal complexes as catalysts immobilized on solid substrates
  • Sara Bals, Antwerp University, Belgium, Advanced TEM characterization of nanomaterials
  • Simon Elliott, Tyndall National Institute, University College Cork, Ireland, Density Functional Theory modelling of ALD processes
  • Jana Zaumseil, Universität Heidelberg, Germany, Nano-carbon optoelectronics, synthesis, materials characterization and device physics
  • Gerwin Gelinck, Holst Centre/TNO and Eindhoven University of Technology, The Netherlands, Nanomaterials for large area flexible displays
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Nanostructured semiconductors: synthesis and characterization : -
09:00
Authors : M. A. McLachlan
Affiliations : Department of Materials & Centre for Plastic Electronics, Imperial College London, London, SW7 2AZ

Resume : Metal oxide semiconductors play an increasingly important role in optoelectronic devices, particularly as charge selective layers in organic photovoltaics. The attraction of metal oxides lies in the unique combination of excellent optical and electronic properties combined with the wide-range of deposition routes that can be implemented for thin film growth. In this presentation I will detail the structural and electrical characterisation of a range of metal oxide thin films prepared using solution and vacuum based deposition techniques. Using the SnO2 and ZnO systems as examples I will highlight the impact simple processing and compositional modifications can have on charge transport, carrier concentration and film resistivity. In both systems the use of relatively high processing temperatures (< 400 C) are typically necessary to ensure crystallinity and optimum properties, a significant disadvantages if they are to be utilised alongside organic semiconductors or any thermally unstable materials. In the final section of the talk I will introduce some recent work we have carried out using ZnO based thin films processed at extremely low temperatures (< 130 C), highlighting the improvements in photovoltaic device performance that can be achieved through subtle modifications in processing temperature. To highlight the versatility of this material we demonstrate its incorporation into both organic and perovskite photovoltaics.

C.1.1
09:30
Authors : A. Momot (1), G. Reekmans (2), P. Adriaensens (2), M.N. Amini (3), R. Saniz (3), D. Lamoen (3), B. Partoens (3), D. R. Slocombe (4), K. Elen (1), A. Hardy (1), M. K. Van Bael (1).
Affiliations : 1 Hasselt University, Institute for Materials Research (IMO), Inorganic and Physical Chemistry, and IMEC vzw, division IMOMEC, Martelarenlaan 42, 3500 Hasselt; 2 Applied and Analytical Chemistry, Institute for Materials Research (IMO), Hasselt University, Agoralaan 1-Building D, BE-3590 Diepenbeek, Belgium 3 University of Antwerp, Department of Physics, Groenenborgerlaan 171, 2020 Antwerp, Belgium; 4 Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, UK, OX1 3QR;

Resume : Aluminium doped zinc oxide (AZO) attracts attention as a tin free transparent conductive oxide. Still, it is unclear how different defects affect its properties. Here, we explore how defects affect conductivity of AZO nanospheres and how they can be tuned by solvolysis synthesis and a post synthesis anneal in nitrogen. The experimental results are supported by first-principle calculations (FPC) that were performed using density functional theory within Perdew–Burke–Ernzerhof functional and the screened hybrid functional of Heyd, Scuseria, and Ernzerhof. The synthesis route is simple using benzylamine as the solvent, and zinc acetylacetonate and aluminium acetylacetonate as precursors. From the results of microwave cavity perturbation technique we conclude, that a combination of prolonged refluxing and annealing leads to highest conductivity. A Knight Shift in NMR indicates the presence of free charge carriers. Raman spectroscopy indicates presence of zinc interstitial clusters in all samples. FPC show that during annealing of the AZO powders interstitial Al dopants move to a substitutional position and form a stable complex with interstitial zinc. The latter result in increased conductivity in AZO. The authors acknowledge the Research Foundation Flanders (FWO project No. G018914) for financial support

C.1.2
09:50
Authors : Claire Verrier, Estelle Appert, Odette Chaix-Pluchery, Laetitia Rapenne, Fares Chouchane, Bassem Salem, Quentin Rafhay, Anne Kaminski-Cachopo, Vincent Consonni.
Affiliations : Université Grenoble Alpes, CNRS, LMGP, F-38000 Grenoble, France Université Grenoble Alpes, CNRS, IMEP-LAHC, Minatec, Grenoble-INP, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LMGP, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LMGP, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LMGP, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LTM, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LTM, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, IMEP-LAHC, Minatec, Grenoble-INP, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, IMEP-LAHC, Minatec, Grenoble-INP, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LMGP, F-38000 Grenoble, France.

Resume : Over the last decade, ZnO nanowires (NWs) have been used for a wide variety of optoelectronic devices, including UV photodetectors and solar cells. For all these applications, their electrical properties, such as their conductivity and mobility, should be controlled as much as possible. ZnO is intrinsically n-type owing to the high density of oxygen vacancies and hydrogen and can intentionally be n-doped, for example, by Al. The doping of ZnO NWs has however been mainly performed by vapor deposition techniques. In the present work, ZnO NWs are doped with Al by using the low-cost, low-temperature, and easily implemented chemical bath deposition (CBD) technique. Aluminum nitrate is added to the standard precursors (i.e. zinc nitrate and HMTA [1]) in deionized water and the [Al(NO3)3] / [Zn(NO3)2] ratio is varied from 0 to 10 %. It is shown by scanning and transmission electron microscopy (TEM) that this addition completely modifies the structural morphology of ZnO NWs. The formation mechanisms are thoroughly investigated and supported by thermodynamic simulations. The incorporation of Al is further investigated by energy dispersive x-ray spectrometry using scanning TEM as well as point probe electrical measurements. Temperature-dependent Raman spectroscopy shows additional modes typically reported in doped-ZnO films and their origins is discussed. [1] R. Parize, J. Garnier, O. Chaix-Pluchery, C. Verrier, E. Appert, and V. Consonni, J. Phys. Chem. C 120, 5242 (2016).

C.1.3
10:10
Authors : Sümeyra Güler-Kılıç, Mehmet Aras, Çetin Kılıç*
Affiliations : Department of Physics, Gebze Technical University, Gebze, Kocaeli 41400, Turkey *Corresponding author: cetin_kilic@gtu.edu.tr

Resume : Doped ZnO nanostructures have attracted considerable interest in recent years owing to their prospective use in a variety of applications including spintronics. This presentation is concerned with the effect of doping ZnO nanowires with a heavy element such as Bi, aiming to reveal the surface-doped ZnO:Bi nanowire as a potential spintronic material. The results of noncollinear spin-density functional theory calculations show that surface doping of ZnO nanowires with Bi leads to a linear-in-k spin splitting of the conduction-band states, through spin-orbit coupling. As noted[1] by the authors recently, Bi in ZnO acts as a donor. The linear-in-k spin splitting is accordingly traced to the interaction of the electrons donated by the Bi dopant with the effective spin-orbit field originating from the inhomogeneous electric field of the ZnO nanowire due to its wurtzite structure. This finding indicates that spin-polarization of electrons in a surface-doped ZnO:Bi nanowire could be controlled with applied electric (as opposed to magnetic) fields since this system exhibits splitting of the spin degeneracy of electronic bands along the momentum axis. Acknowledgement: Work supported by TUBITAK through Grant No. 114F155. [1] Kilic C, Aras M, Guler-Kilic S 2016, “Computational studies of bismuth-doped zinc oxide nanowires” in Low Dimensional and Nanostructured Materials and Devices, eds H Unlu, NJM Horing, J Dabrowski, Springer International Publishing, Switzerland, ch. 16.

C.1.4
10:30 Coffee break    
 
Nanostructured semicondutors: synthesis and characterization : -
11:00
Authors : Salvatore Cosentino1, Giorgia Fiaschi2, Vincenzina Strano3, Ting-Wei Liao1, Anupam Yadav1, Nofar Mintz-Hemed2, Salvo Mirabella3, Didier Grandjean1, Peter Lievens1, Yosi Shacham-Diamand2
Affiliations : 1 Laboratory of Solid-State Physics and Magnetism, KU Leuven, Leuven, Belgium 2 Department of Physical Electronics, Tel Aviv University, Tel Aviv, Israel. 3 CNR-IMM and Dipartimento di Fisica ed Astronomia, Università di Catania, Catania, Italy

Resume : ZnO Nano-Rods (NR) are a fascinating material for sensing applications because of their large surface area and high concentration of electrically active defects. The incorporation of metal nanoclusters (NC) can add further benefit through modification of the active electronic states at the NR-NC interface. For this reason, here we report a detailed electrochemical characterization of ZnO NR electrodes decorated with mono- and bimetallic NC. ZnO NR having a mean diameter of 100 nm and height of 800 nm were grown by chemical bath deposition on n-Si and ITO conductive substrates. Controlled amounts of Au, Pt and AuPt NC, with size smaller than 5 nm, were deposited on ZnO NR. NC were produced by laser ablation of a metallic target and condensation in a pulsed high pressure He carrier gas with subsequent beam deposition in vacuum [1]. Electrochemical impedance spectroscopy (EIS) was used to probe the interfacial states of the NC-modified ZnO electrodes. Charge-transfer resistance and interface capacitance were estimated through modeling of EIS curves for different bias regimes. ZnO NR reveals a large amount of active surface states (~10^20 cm-3), which are dramatically altered after incorporation of NC. The change in the capacitance and charge-transfer process strongly depends on the type of NC. Our results are elucidated taking into account the different band alignment at the interface between ZnO NR and Au, Pt and AuPt NC. [1] W. Bouwen et al. Rev. Sci. Instrum. 71, 54 (2000)

C.2.1
11:15
Authors : Stephanie Bley, Alejandra Castro-Carranza, Emily Tansey, Wilken Seemann, Jürgen Gutowski
Affiliations : Institute of Solid State Physics, Semiconductor Optics, University of Bremen, Bremen 28359, Germany

Resume : Core/shell nanowires with inorganic ZnO cores and organic p-conductive polymer shells possess huge potential for the realization of efficient light-emitting and photovoltaic devices. A controlled deposition of the polymer shell in the nm range is required to tailor the electrical and optical properties. Spin coating of polymers on ZnO nanowires is a suitable method to create pn-heterojunctions by conformal coating of the nanowires in the nanometer range. In our case, PEDOT:PSS and PTB7 on ZnO nanowire arrays are used to form hybrid heterojunctions. Both p-type polymers are well-known for their stability and highly absorbent properties, respectively. However, in general, wet-chemical methods as used for this purpose lead to defects at the interface which lower the quality of the desired diode. To decrease the number of defects at the interface, an additional thin insulating passivation layer with high transparency is necessary. For this purpose, we used polystyrene (PS) as such an interlayer deposited on the hybrid structure by spin coating. Its thickness is systematically modified to study its impact on defect state passivation at the heterojunction interface, which is characterized by measuring the structural, optical, and electrical performance of the thus obtained heterojunctions.

C.2.2
11:30
Authors : Giorgio Carraro,1 Chiara Maccato,1 Alberto Gasparotto,1 Kimmo Kaunisto,2 Cinzia Sada,3 Davide Barreca4
Affiliations : 1 Department of Chemistry, Padova University and INSTM, 35131 Padova, Italy; 2 Department of Chemistry and Bioengineering, Tampere University of Technology, 33101 Tampere, Finland; 3 Department of Physics and Astronomy, Padova University, 35131 Padova, Italy; 4 CNR-ICMATE and INSTM, Department of Chemistry, Padova University, Padova, Italy.

Resume : Iron-cobalt oxide nanocomposites have drawn a growing attention for various applications, such as heterogeneous (photo)catalysts, sensors and anodes for photoelectrochemical (PEC) cells aimed at solar H2 production. In this work, Fe2O3-Co3O4 nanomaterials were prepared by a plasma-assisted approach, consisting in: (i) plasma enhanced-chemical vapor deposition (PE-CVD) of Fe2O3 nanosystems on conducting glass substrates; (ii) Co3O4 functionalization by radio frequency sputtering.1 In addition, the effects of thermal annealing in air were studied by a multi-technique chemico-physical investigation. The obtained nanomaterials were characterized by a tailored coverage of Fe2O3 matrices by Co3O4 nanoaggregates, resulting in an intimate Fe2O3-Co3O4 contact and in a cobalt oxide loading tuneable by variation of the sputtering time. Interestingly, PEC performances in solar water oxidation were directly dependent on Co3O4 loading and distribution in the target systems. An appreciable photocurrent increase (40%) and cathodic onset potential shift (50 mV) were achieved for Fe2O3-Co3O4 nanomaterials with respect to bare Fe2O3. The obtained results validate the developed plasma-assisted strategy as an efficient route to exploit the favourable Co3O4 influence on Fe2O3 photoanode performances. The present route can also be extended to a variety of oxides, paving the way to the development of PEC anode materials with improved photoactivity. 1 G. Carraro et al., Plasma Processes Polym., 2016, 13, 191.

C.9.4
11:45
Authors : Negar Gheshlaghi (a); Hadi Sedaghat Pisheh (a); Hilmi Ünlü (a,b)
Affiliations : (a) Nanscience and Nanoengineering Programme, Institute of Science and Technology İstanbul Technical University, Maslak Istanbul 34469 TURKEY (b) Department of Physics, Faculty of Science and Letters İstanbul Technical University, Maslak Istanbul 34469 TURKEY

Resume : Colloidal semiconductor quantum dots (QDs) have the advantages of high stability, solution processability, tunable emission wavelength and high color saturation. In the broad application of QDs, light-emitting diodes (LEDs) based on colloidal QDs have attracted considerable interest in the past few years for use in flat panel displays and solid state lighting. ZnSe based quantum dots (QD) are semiconductor nanocrystals that possess unique optical properties and they are the potential candidate for next generation LEDs and photovoltaic devices. Their emission color can be tuned from the visible throughout the infrared spectrum. In this work we report a synthetic route to prepare type-I and type-II core/shell ZnSe/Zn(Cd)S and core/shell/shell ZnSe/Zn(Cd)S/Cd(Zn)S colloidal spherical quantum dots. The synthesized nanocrystals were characterized by using high resolution TEM and x-ray diffraction (XRD) for structural properties and UV absorption and fluorescence techniques for optical properties. The effects of lattice mismatch induced interface strain on the first exciton energy, capped core diameter and conduction and valence band energies of the quantum dots investigated. The induced interface strain from lattice mismatch between core and shell(multishell) calculated from continuum elastic theory and applied in effective mass aproximation (EMA) to calculate corresponding capped core diameter. The results compared with bare core images from TEM to evaluate squeeze (stretch) amount in core size after compressive (tensile) shell deposition.

C.2.4
12:00
Authors : Ran Eitan Abutbul, Vladimir Ezersky, Yuval Golan
Affiliations : 1. Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel 2. Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel

Resume : Scientific background: π-SnS is a new binary phase in the Sn-S system. It was discovered in the form of tetrahedral nanoparticles, present in small amounts among the reaction products. Selected area electron diffraction (SAED) patterns didn’t confirm the conventional phase of tin sulfide however; these patterns could be readily indexed if a large cubic and primitive lattice is considered. Obtaining a full structure solution for the π-SnS phase (P213, a0=11.7 Å) was enabled through precession electron diffraction tomography (PEDT) technique. Because of π-SnS phase was just discovered and only in diluted mixtures with conventional SnS, its properties remained unknown up to this point 1 Results: We report on the synthesis of the newly discovered cubic phase of tin sulfide, π-SnS, obtained in the form of surfactant capped nanoparticles and compare its properties to the well- known phase of tin sulfide, α-SnS. Shape control was achieved by variation of synthesis parameters, resulting in cubic, rhombic dodecahedral and tetrahedral shapes of the π-SnS nanoparticles. X-ray diffraction provided authentication of the proposed model and refined determination of the lattice parameter a0=11.595 Å. Optical absorption spectroscopy indicated an indirect band gap of 1.53 eV, in good agreement with density functional theory (DFT) calculations indicating a band gap greater than that of a-SnS.2 The research was extended to explore the possibility of the existence of analogues structure of π-SnS in the Sn-Se system. In the modified synthesis protocol we have used selenourea as the selenide precursor to synthesize SnSe nanoparticles. We found that in a similar fashion to the SnS case, the orthorhombic phase was dominant at higher temperatures. At low temperature regime the XRD diffractogram could not be indexed to the orthorhombic phase of SnSe which indicate a different crystal structure. TEM examination of the particles revealed that they appear to be cube shaped. HRTEM of those particles along major zone axes showed net symmetry patterns which could only be fully indexed if a large cubic crystal structure is considered. By adopting the structural model of π-SnS and replacing S atom by Se we established a new model which could account for both XRD results and the HRTEM micrographs.3 collaborated research with Prof. Nair's group from UNAM Mexico has shown that π-SnS is not limited only to surfactant capped nanoparticles but could also account for deposition of nanocrystalline thin films. Theoretical research of this unique phase also predicts potentially useful optical and physical properties which are not expected from the conventional phase of tin sulfide.4 References: 1. Rabkin, A.; Samuha, S.; Abutbul, R. E.; Ezersky, V.; Meshi, L.; Golan, Y. New Nanocrystalline Materials: A Previously Unknown Simple Cubic Phase in the SnS Binary System. Nano Lett. 2015, 15 (3), 2174–2179. 2. Abutbul, R. E.; Segev, E.; Zeiri, L.; Ezersky, V.; Makov, G.; Golan, Y. Synthesis and Properties of Nanocrystalline π-SnS – A New Cubic Phase of Tin Sulphide. RSC Adv. 2016, 6 (7), 5848–5855. 3. Abutbul, R. E.; Segev, E.; Samuha, S.; Zeiri, L.; Ezersky, V.; Makov, G.; Golan, Y. A New Nanocrystalline Binary Phase: Synthesis and Properties of Cubic Tin Monoselenide. CrystEngComm 2016, 18 (11), 1918–1923. 4. Abutbul, R. E.; Garcia Angelmo, A. R.; Burshtein, Z.; Nair, M. T. S.; Nair, P. K.; Golan, Y. Crystal Structure of a Large Cubic Tin Mono-Sulfide Polymorph: An Unraveled Puzzle. CrystEngComm 2016, DOI: 10.1039/C6CE00647G.

C.2.5
12:15
Authors : F. Bassani1, V. Gorbenko1,2, J. Roque1,2, R. Alcotte1, S. David1, M. Martin1, J. Moeyaert1, J.-P. Barnes2, E. Martinez2, W. Hourani2, N. Bernier2, N. Rochat2, C. Guedj2, A. Grenier2, G. Audoit2, Y. Bogumilowicz2, E. Sanchez3, T. Baron1
Affiliations : 1 Univ. Grenoble Alpes, LTM, F-38000 Grenoble, France CNRS, LTM, F-38000 Grenoble, France 2 Univ. Grenoble Alpes, F-38000 Grenoble, France CEA-LETI, MINATEC Campus, F-38054 Grenoble, France 3 Applied Materials, Santa Clara, California, United States

Resume : The evolution of semiconductor devices architecture towards non-planar structures makes characterization extremely challenging. Monolithic integration of III-V light-emitting sources with Si photonic circuits is highly desirable because it can dramatically enhance performance for chip-to-chip and on-chip wireless communications. However, direct epitaxial growth of III-V materials on Si presents many difficulties, mainly because of the large lattice mismatch and the polar/non-polar character of layer/substrate interface thereby generating numerous structural defects such as dislocations and antiphase domain boundaries (APBs). This is the reason why currently III-V laser sources are reported on Si via bonding. Recently, we have demonstrated that high structural quality InGaAs quantum wells (IGA QWs) selectively grown on patterned Si substrates using the aspect ratio trapping method exhibit room temperature tunable light emission by adjusting the In composition [1]. In this work, we will present the structural and chemical characterization of these IGA QWs. Different characterization techniques (ToF-SIMS, Auger, STEM-EDX, STEM-HAADF, APT, precession electron diffraction, cathodoluminescence) have been used and developed to obtain accurate information on the 3D spatial distribution of chemical elements at the nanoscale, interfaces abruptness, In quantification [2,3,4], and correlate light emission properties with the presence of structural defects and strain in these selectively grown IGA QWs [5]. [1] R. Cipro et al., Low defect InGaAs quantum well selectively grown by metal organic chemical vapor deposition on Si(100) 300mm wafers for next generation non planar devices, Appl. Phys. Lett. 104, 262103 (2014) [2] V. Gorbenko et al., Chemical characterization of III–V heterostructures in 3D architecture, Microelectronic Engineering 147, 219 (2015) [3] V. Gorbenko et al., Ultra-high resolution SIMS depth profiling and 3D reconstruction of III-V heterostructures for advanced 3D architecture nanoelectronic devices, PSS-RRL 9, 202 (2015) [4] W. Hourani et al., 3D Auger quantitative depth profiling of individual nanoscaled III-V heterostructures, submitted [5] S. David et al., Spatially correlated structural and optical characterization of a single InGaAs quantum well fin selectively grown on Si by microscopy and cathodoluminescence techniques, to be published in APL Materials

C.2.6
12:30 Lunch break    
 
Nanostructured semicondutors for emerging devices : -
14:00
Authors : Gerwin Gelinck
Affiliations : 1Holst Centre, High Tech Campus 31, 5656 AE Eindhoven, Eindhoven, The Netherlands 2Applied Physics Department, TU Eindhoven, Eindhoven, The Netherlands

Resume : Flexible amorphous oxide semiconductor thin-film transistors are viewed as an important technology for a broad range of emerging electronic applications. Today, the long-held dream of rollable and foldable displays is driving this innovation, but it is without a doubt that as the technology matures, other applications will be realized. For example, curved X-ray detectors and other medical devices such as skin patches, and wireless nfc playing cards, disposable food and medication sensor packages. This presentation introduces the materials and processes required to fabricate amorphous oxide transistors on plastic foils, offering advantages in terms of process simplification and device performance. I will explain why a better understanding of these materials and devices – in terms of possibilities and limitations - is needed in order for them to be used in next-generation mobile and wearable electronics, focusing on both electrical as well as mechanical aspects. I will show examples how the development new fabrication processes enable new amorphous oxide semiconductor materials and novel device concepts.

C.3.1
14:30
Authors : Ivan Isakov, Hendrik Faber, Max Grell, Das Satyajit and Thomas D. Anthopoulos
Affiliations : Imperial College London

Resume : Solution processed metal oxide thin film transistors (TFTs) are promising candidates for the use in ubiquitous flexible electronics due to their low cost, high charge carrier mobility and optical transparency. However, in order to be able to compete with the incumbent amorphous and polycrystalline silicon, the metal oxides TFTs should simultaneously overcome the charge carrier mobility limit of 30-50 cm2/Vs and be processed in air at temperatures below 300 °C (compatible with flexible polyimide films). Recently, our group has achieved unprecedented electronic performance in ultrathin indium oxide thin film transistors deposited from solution via ultra-sonic spray pyrolysis [1] and in multilayer metal oxide thin films prepared from solution via spin-coating [2], with electron mobility reaching up to 20 and 40 cm2/Vs, respectively. Building on the previous results, here we report routes to further improve electrical performance of spray-coated In2O3 devices by optimising growth conditions and by fabricating In2O3/ZnO bilayers. First, we investigate the nucleation and formation of the In2O3 film by thoroughly correlating deposition parameters, film morphology, computer simulation results and electronic properties of the thin film. As a result we propose a prescription for the high performance ultrathin In2O3 TFT fabrication by spray pyrolysis with a possibility to tune threshold voltage and to reach electron mobility up to 35 cm2/Vs. Second, we study bilayer TFTs prepared from spray-coated In2O3 bottom layer with various ZnO-containing top layers. We show that the In2O3/ZnO interface dramatically enhances electronic performance of the oxide TFTs, with electron mobility reaching up to 50-55 cm2/Vs. In order to understand the underlying mechanism of this radical improvement, we perform temperature-dependent transistor and Hall measurements. [1] H Faber et al - ACS Appl. Mater. Interfaces, 2015, 7 (1), pp 782–790 [2] Y-H Lin et al - Adv. Sci., 2015, 2, 1500058

C.3.2
14:50
Authors : D. De Sloovere, W. Marchal, F. Ulu, M.K. Van Bael, A. Hardy
Affiliations : Hasselt University, Institute for Materials Research, Inorganic and Physical Chemistry, Martelarenlaan 42, 3500 Hasselt, Belgium. E-mail: an.hardy@uhasselt.be; IMEC vzw, Division IMOMEC, Agoralaan Building D, 3590 Diepenbeek, Belgium

Resume : While using LTO as the anode in lithium ion batteries greatly enhances their operation safety and avoids the formation of a solid electrolyte interface, the synthesis of this material often comes at a high time and energy cost. A typical solid-state synthesis method requires the reagents to be kept at temperatures up to 900°C for several hours. Both synthesis temperature and processing time were reduced by applying the concept of solution combustion synthesis. In this method, a precursor is synthesized which generates the energy needed for complete sample conversion and crystallization in an exothermic reaction. The thermal decomposition of the precursor was characterized by TGA/DSC and the phase composition and particle size of the thermally processed powder were determined by FT-IR, XRD, TEM and DLS. The synthesized powders were tested for their electrochemical characteristics. By using the concept of combustion synthesis, the synthesis temperature was reduced to 300°C, while the time required was reduced to minutes. The synthesized material consisted mainly of LTO with small amounts of impurities. The discharge capacity of this material with a theoretical capacity of 175 mAh/g was 165 mAh/g at 0.1C, decreasing to 158 mAh/g after 40 cycles. At 1C, the discharge capacity was 140 mAh/g. This good rate capability is explained by the small size (200-300 nm) of the product, though there were also agglomerates. This work was supported by FWO G041913.

C.3.3
15:10
Authors : Jonathan Van Den Ham, Marlies K. Van Bael Giulia Maino,An Hardy
Affiliations : Hasselt University, Institute for Materials Research, Inorganic and Physical Chemistry, Diepenbeek, Belgium and IMEC, Division IMOMEC, Diepenbeek, Belgium

Resume : Lithium ion batteries (LIB) have important applications for mobile IT, electric transportation or storage of renewable energy. Conventional LIB are using powder based electrodes and a liquid electrolyte, and provide high capacity. Alternatively, thin film LIB provide higher power and employs solid electrolytes, which guarantees safety. 3D thin film batteries are proposed to enhance the energy density of the latter. Here, we discuss wet chemical synthesis routes applied to planar and 3D thin film batteries. We discuss a solution based deposition process for planar and 3D thin film battery components, including anode (TiO2, Li4Ti5O12, WO3), cathode (LiMn2O4) and solid electrolytes (Li3xLa(2/3)-x?(1/3)-2xTiO3) as well as half cells. A homogeneous, highly conformal deposition is obtained by an optimized ultrasonic spraydeposition process of a water based precursor solution containing citrate complexes, with finetuned surface tension and gelation upon contact with the substrate. The morphology, crystal structure, chemical purity and electrochemical properties are characterized, showing a 3 fold increase in the capacity by the areal increase in the 3D structured thin film half cell. We acknowledge the EFRO project 936, IWT project SBO SOSLION and UHasselt (BOF-IOF) for financial support.

C.3.4
15:30 coffee break    
 
Atomic layer deposition of nanomaterials : -
16:00
Authors : Woochool Jang, Hyunjung Kim, and Hyeongtag Jeon
Affiliations : Division of Materials Science and Engineering, Hanyang University, Seoul 133-791, Korea; Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791, Korea; Division of Materials Science and Engineering, Hanyang University, Seoul 133-791, Korea;

Resume : Gate sidewall spacer in sub-micron semiconductor device is important to control the source/drain doping profiles and to suppress the short channel effect. As the dimensions of devices continue to shrink, one of demands for gate spacer is low temperature process to retard the degradation of the short channel margin. Another is excellent step coverage. Atomic layer deposition (ALD) is an ideal solution for achieving the high conformality due to its self-limited reaction. The introduction of plasma is also required to meet low temperature process. However, direct plasma may cause the substrate damage due to its ion bombardment. Remote plasma ALD (RPALD) is used to avoid the possible substrate damage. Silicon nitride and silicon oxycarbide have attracted much attention because they are suitable materials as a gate spacer due to its superior thermal stability, chemical and electrical properties. In this presentation, we will discuss the current state of silicon nitride and oxycarbide ALD and report the results of silicon nitride with various precursors and oxycarbide with various plasmas such as O2, Ar, and H2 .

C.4.1
16:30
Authors : Anne Tanskanen, Maarit Karppinen
Affiliations : Department of Chemistry, Aalto University, Finland

Resume : Atomic layer deposition (ALD) is well-known as a sophisticated technique to deposit conformal thin films with precisely controlled thicknesses. Moreover, it is a very versatile tool for innovative material research where interfacial effects can be utilized. Molecular layer deposition (MLD) is a variation of ALD where molecular organic layers are deposited instead of atomic layers. These two techniques can be combined as one process (ALD/MLD) resulting in new inorganic-organic hybrid thin films where metal atoms are chemically bound to organic molecules. Combining inorganic-organic hybrid materials and inorganic oxides as thicker blocks or just adding organic molecular layers into inorganic oxide matrix it is possible to modify the properties of the materials in a delicate and well-controlled way. In this study, the focus is on iron-based materials deposited by ALD or ALD/MLD technique. ALD is used to realize thin films of the rare crystal structure of iron oxide (ε-Fe2O3), deposited by using FeCl3 and water as precursors. The pure ε-Fe2O3 phase has been difficult to synthesize via wet chemical techniques and it has been discussed to be dependent on the small particle size and thus the surface forces. It is interesting due to its magnetic properties. When including organic terephthalic acid (TPA) molecules in the FeCl3-H2O process the crystal structure of the films gradually changes to α-Fe2O3 (hematite). The frequency of organic molecular layers can be controlled and thus the properties of the hematite can be modified. An exciting outcome is achieved when FeCl3 and TPA are combined into one-to-one hybrid material as the product is found to form a porous crystalline metal organic framework (MOF) structure. Here the organic network separates the iron atoms to create a larger surface area for iron species that is an apparent advantage in e.g. catalytic applications.

C.4.2
16:45
Authors : Jan Willem Maes
Affiliations : ASM Belgium, Kapeldreef 75, 3001 Leuven, Belgium

Resume : Atomic Layer Deposition (ALD) nowadays is a key process in the fabrication of advanced semiconductor devices. This is the result of the specific features and benefits of ALD: high-precision deposition of high quality and highly conformal ultra-thin films at low temperatures. Examples of ALD processes previously developed by us and currently being used in CMOS logic devices are ALD high-k dielectrics and metallic work function layers for the gate stack, PEALD layers for solid state doping and PEALD metal oxides for spacer defined double patterning. Some key features of innovative ALD manufacturing tools developed for these films will be discussed. Further increasing the number of transistors in integrated circuits involves scaling the dimensions of devices and introducing new materials and new 3D architectures. The key inflection points on the roadmap for the upcoming Logic technology nodes will be reviewed showing that ALD technology is a key enabler of Moore’s Law and that the demand for ALD layers is expected to further increase. Several of the ALD layers and processes under development for future nodes will be discussed in more detail such as new patterning assist layers, new interface layers for high mobility channel materials and area selective ALD processes.

C.4.3
17:15
Authors : C. Frijters 1, P.J. Bolt 1, P. Poodt 1, R. Knaapen 2, J. van den Brink 2, M. Ruth 3, D. Bremaud 3, A. Illiberi 1
Affiliations : 1 Solliance/TNO, Eindhoven, 5656AE, The Netherlands, 2 VDL Enabling Technologies Group, 5651GG, Eindhoven, The Netherlands, 3 Flisom AG, Uberlandstrasse 129, 8600 Dubendorf, Switzerland

Resume : Zn(O,S) has emerged as a valid alternative to the CdS buffer layer, because the use of toxic Cd is avoided and the quantum efficiency of the cells is enhanced in the blue wavelength region. Atomic layer deposition (ALD) is an ideal technique for the growth of Zn(O,S) buffer layers. However, the low deposition rate (≈ 0.01 nm/s) of ALD can hinder its use in the solar cell industry where high-throughput is needed to achieve low production costs. This drawback has been overcome by the spatial ALD technique (S-ALD), which combines high deposition rates (up to nm/s) with the advantages of conventional ALD. A deposition process for Zn(O,S) has been developed in a lab-scale S-ALD reactor for rigid 15x15 cm2 rigid substrates. Next, the deposition process for Zn(O,S) has been transferred to a roll-to-roll S-ALD set-up built by VDL which handles 50 cm wide flexible substrates. The optoelectronic and morphological properties of Zn(O,S) are characterized as a function of the S/(S+O) ratio and they are optimized for application as buffer layer in CIGS solar cells. An efficiency of 16 % is achieved in 0.50 cm2 CIGS cells on glass for S/(S+O) = 0.4, which is higher than the efficiency of the reference cells with CdS. Flexible CIGS modules with roll-to-roll S-ALD Zn(O,S) buffer layer have an efficiency of 9.2 %. These results prove the viability of spatial ALD as a new manufacturing technique to engineer the electrical properties of interfaces in flexible CIGS solar cells.

C.4.4
 
Poster Session 1 : -
17:30
Authors : Seongkyung Kim, Hajin Lim, Joon-Rea Kim, Jea Kyeong Jeong, and Hyeong Joon Kim
Affiliations : seoul national university

Resume : For sub-10 nm logic MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), III-V compound materials and Ge have attracted huge attention as strong candidates for channel materials due to their high mobility. Even though Ge devices have been studied mostly for p-channel, it has critical issues such as water solubility and hygroscopic property of its native oxides. CMOS (complementary-metal-oxide-semiconductor) technologies based on III-V compound materials are facing the issues for co-integration of III-V and IV materials. For those problematic issues, GaSb is a promising material for p-channel devices since it has the highest hole mobility among III-V compound materials (1000 cm2/V.s) and its native oxides do not dissolve in water. GaSb makes strong inversion and ohmic contact easily, and has high effective density. Nevertheless, III-V materials have challenges to overcome for interface engineering such as achieving low interface state trapped charge. There is a great concern to GaSb which is its inherent susceptibility to air exposure. To put it simply, GaSb forms native oxides quickly within ambient air exposure and these oxides are not stable. Because of high interface state trapped charge from the unstable native oxides, III-V materials including GaSb show Fermi-level pinning behavior. Various chemical wet and dry cleaning methods have been researched to clean the surface and alleviate the surface native oxides, thereby improving the electrical properties of the interface between high-k oxides and GaSb. HCl and plasma treatments are told as the most effective ways to alleviate the surface oxides. However, the most effective chemical for surface cleaning, HCl, cannot or barely eliminate Sb2O5. The remaining Sb-oxide oxidizes Ga to Ga-oxides and turns into elemental Sb. Furthermore, for ex-situ deposition which requiring air exposure before depositing high-k oxides on top of GaSb, these further oxidation of the native oxides after chemical cleaning is problematic. There are, currently, few research on combined treatments of (NH4)2S and HCl. Even though, using (NH4)2S is a good way to prevent further oxidation with terminating the surface with S, the further oxidation occurs while gate oxides are deposited in a chamber. For eliminating the remaining oxides, therefore extra surface cleaning should be considered. There are studies about the effects of heating GaSb in an UHV(Ultra High Vacuum) system. A clean and flat surface can be obtained easily with heating GaSb in UHV system at very high temperature (~ 500 ℃) in the end. In this study, rather than setting up UHV, RTP(Rapid Thermal Process) under nitrogen atmosphere was firstly adopted to eliminate the remaining native oxides and elemental Sb. Since RTP does not require UHV, less time and efforts are needed compare to heating GaSb in UHV system. Also nitrogen gas can alleviate the surface oxidation. (NH4)2S and HCl were used to clean the surface after degreasing it with acetone, ethanol, IPA (Iso propane Alcohol). RTP for cleaning the surface was performed in various temperatures. 10 nm of Al2O3 was deposited on top of it with ALD (Atomic Layer Deposition) and then 1000 Å of Pt was deposited with an e-beam evaporator. Normalized capacitance versus voltage curves and Terman method were used for verifying the degree of Fermi-level pinning behavior and density of interface trap respectively. XPS and AES were used to confirm interface properties between Al2O3 and GaSb. As a result, the Fermi-level pinning behavior was successfully alleviated with the RTP cleaning. This improved electrical property seems from increased Ga2O3/Ga2O ratio which is verified with XPS. It shows the lowest Dit value (1.06×〖10〗^12 〖cm〗^(-2) 〖eV〗^(-1)) at 575 ℃ of RTP cleaning temperature among the samples which were treated with sulfur passivation in literature. However, it is higher than ones from hydrogen plasma treatment since it is ex-situ process while hydrogen plasma treatment is in-situ process.

C.P1.1
17:30
Authors : O. Gorban, I.Danilenko, S.Gorban, E.Zhitlukhina, K. Lamonova, G.Volkova, T. Konstantinova
Affiliations : Donetsk Institute for Physics and Engineering named after O.O.Galkin NAS of Ukraine, Prospect Nauki, 46, Kiev-03039, Ukraine

Resume : Multicomponent based zirconia or ceria composite nanosystems are promise materials for application in environmental media, medicine etc. As specific feature of composite materials is the crucial effect the interface on their structural, electronic, optical and other properties. In case these oxide composite nanosystems formation of complex nanoparticles takes place thorough interface controlling processes such as dehydration, dehydrogenization, destruction, crystallization and growth during of heat-treatment process. In this connection, interface may be effective key for controlling properties of nanosystems. The wide spectrum of materials from pure zirconia (or ceria) to complex systems based on zirconia was investigated in this work. It was discussed influence on structural and electronic properties zirconia introduction in interface the different kinds of anions, cations of d-, f-elements and their complexes, and also polymeric molecules. The features of interconnection interface and volume in complex systems with different structure organization – core/shell, NPs in matrix were study. The possible ways of reorganization of complexes of d-,f-elements in interface during temperature and reduction action were estimated. The role of interface in forming structure and properties complex nanosystems and the mechanisms of forming of these systems and its properties are discussed. The work particular carried out in frameworkH2020 Program “NANOGUARD2Ar”.

C.P1.2
17:30
Authors : E. A. Anumol (a), Andrey Enyashin (b), Nitin M. Batra (c), Pedro M. F. J. Costa (c) and Francis Leonard Deepak (a), *
Affiliations : a. International Iberian Nanotechnology Laboratory (INL), Avenida Mestre Jose Veiga, Braga 4715-330, Portugal, E-mail: leonard.francis@inl.int b. Ural Federal University, Institute of Mathematics and Computer Sciences, Turgeneva Str., 4, 620083 Ekaterinburg, Russian Federation c. King Abdullah University of Science and Technology, Physical Science and Engineering Division, Thuwal 23955-6900, Saudi Arabia

Resume : The hollow interiors of nanotubes could host the growth or filling of foreign elements or compounds to obtain hetero-structures. The growth of these materials in the confined one dimensional space lead to novel properties. Capillary filling serves as a method to enable filling of carbon nanotubes and inorganic nanotubes including those of BN and WS2.1, 2 In this work, considering the biocompatibility of WS2 and paramagnetic property of gadolinium (III) compounds, capillary filling is employed to obtain GdX3@WS2 nanotubes (X=Cl, Br, I). Gadolinium based compounds find important applications in medical imaging and diagnosis. Thus the precise determination of the structure and composition is detrimental in its further application. In the present case the morphology, structure and chemical composition of the synthesized GdI3 filled WS2 NTs is investigated using aberration corrected scanning/transmission electron microscopy and associated spectroscopic techniques (Electron Energy Loss Spectroscopy (EELS) and Energy Dispersive X-Ray Analysis (EDS)). The three-dimensional morphology is investigated using STEM tomography but obtaining three dimensional compositional information is non-trivial due to the presence of multiple high atomic number elements. Therefore, EDS-STEM tomography3 is employed to map the chemical composition in three dimensions. In order to reduce the beam induced effects on the specimen, tomography experiments were carried out at 80 kV in the present case. In view of the long duration of electron beam exposure necessary to perform EDS-STEM tomography, electron irradiation studies are carried out to optimize the EDS-STEM tomography conditions. The experimental observations are adequately supported by carrying out Molecular Dynamics Simulation in order to elucidate the difference in behavior of the various halides (GdI3 vs GdCl3 vs GdBr3) towards their affinity to fill the interior of the WS2 Nanotubes.4 References [1]. Ronen Kreizman, Andrey N. Enyashin, Francis Leonard Deepak, Ana Albu-Yaron, Ronit Popovitz-Biro, Gotthard Seifert, and Reshef Tenne, Adv. Funct. Mater., 20 (2010) 2459–2468. [2]. Elok Fidiani, Pedro M. F. J. Costa, Anja U. B. Wolter, Diana Maier, Bernd Buechner, and Silke Hampel, J. Phys. Chem. C, 117 (2013) 16725−16733. [3]. Georg Haberfehlner, Angelina Orthacker, Mihaela Albu, Jiehua Li and Gerald Kothleitner, Nanoscale, 6 (2014) 14563–14569. [4]. E. A. Anumol, Andrey Enyashin, Nitin M. Batra, Pedro M. F. J. Costa and Francis Leonard Deepak, Nanoscale, 2016, DOI: 10.1039/c6nr02710e.

C.P1.3
17:30
Authors : Michaela Meyns, Svenja Willing, Hauke Lehmann, Christian Klinke
Affiliations : Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany

Resume : Thin films prepared of semiconductor nanoparticles are promising for low-cost electronic applications such as transistors and solar cells. One hurdle for their breakthrough is their notoriously low conductivity. To address this, we precisely decorate CdSe nanoparticles with platinum domains of one to three nanometers in diameter by a facile and robust seeded growth method. We demonstrate the transition from semiconductor to metal dominated conduction in monolayered films. By adjusting the platinum content in such solution-processable hybrid, oligomeric nanoparticles the dark currents through deposited arrays become tunable while maintaining electronic confinement and photoconductivity. Comprehensive electrical measurements allow determining the reigning charge transport mechanisms. Reference: Michaela Meyns, Svenja Willing, Hauke Lehmann, Christian Klinke: Metal domain size dependent electrical transport in Pt-CdSe hybrid nanoparticle monolayers, ACS Nano 9 (2015) 6077.

C.P1.4
17:30
Authors : Wipakorn Jevasuwan, Thiyagu Subramani, Toshiaki Takei and Naoki Fukata
Affiliations : International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS)

Resume : Core-shell nanowire (NW)-based solar cells and gate all around NW-field-effect transistors are hot research topics for advanced technology at this moment. Vapor-liquid-solid mechanism of chemical-vapor-deposition technique is one of candidates to create NW structures. Although several Au-catalyzed NW formations have already been reported [1,2], they are difficult to realize high performance devices owning to Au contamination. In this study, we would like to present Al which has been recently proposed as a new alternative catalyst [3] to form SiNWs. SEM, TEM, and Raman spectroscopy were applied for characterizations. All SiNW samples were carried out using n-Si(111) substrate and the 50-nm-thick Al-catalyst films were prepared using sputtering. SiNW formation was performed with various substrate temperatures of 550 °C, 600 °C, 650 °C, and 700 °C. SEM images showed that SiNWs can be formed at 600 °C and good vertical taper-shaped SiNW structure was achieved at 650 °C. Adding of non-directional SiNW branch was more obvious at 700 °C. TEM images revealed that amorphous Si and remaining Al catalyst were observed at SiNW surface and on the top of SiNW, respectively. Single-crystal Si growth was detected inside SiNW and SiNW formation was shown along [111] direction. Raman spectroscopy detected good crystal uniformity SiNWs grown at 650 °C and 700 °C. Fano-effect was observed and Al doping concentration was also examined. [1] N. Fukata, et al., Nanoscale, 7 [16] (2015) 7246-7251, [2] N. Fukata, et al., ACS Nano, 6 [4] (2012) 3278-3283 [3] Y. Wang, et al., Nature Nanotech., 1 (2006) 186-189.

C.P1.5
17:30
Authors : Changyun Moon*,**, Sungjin Kim*, Taewoo Jeon*, Sangouk Kim*
Affiliations : *Department of Materials Science and Engineering, KAIST, Daejeon, Republic of Korea **Samsung Display, Republic of Korea

Resume : Nowadays current display industries are focusing on the development of high efficiency and low cost display materials. Perovskite materials are emerging as new generation material for LEDs because of their low cost, simple band gap tuning, excellent charge carrier mobility and simple processing at low temperature. It was reported that solution processing is an apt method for the synthesis of uniform surface perovskite film, which is beneficial for better electro-luminance efficiency of perovskite light emitting diodes (PeLEDs). In addition structure and band diagram in PeLEDs plays an important role in the efficiency of PeLEDs and optimization of the same is still lacking. In this work we have fabricated a uniform perovskite MAPbBr3 thin films using nanocrystal pinning of chlorobenzene during spin coating and vacuum annealing. SEM images indicates that spin coating rate and annealing give us uniform and continues morphology. Moreover we have used Bathocuproine (BCP) as deep HOMO level Hole Blocking layer (HBL) and electron transport layer (ETL) to fabricate green PeLEDs. High efficiency of MAPbBr3 device is achieved with 14000 cd/m2 at 5.5 V with a high current efficiency (CE) which is far much better than reported values.

C.P1.6
17:30
Authors : Wook Kim 1, Jang-Yeon Kwon 2, Dukhyun Choi 1,3
Affiliations : 1 Department of Mechanical Engineering, College of Engineering, Kyung Hee University, 1732, Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, Republic of Korea 2 School of Integrated Technology, Yonsei University, 162-1, Songdo-dong Yeonsu-gu, Incheon, 406-840, Republic of Korea 3 Industrial Liaison Research Institute, Kyung Hee University, 1732, Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, Republic of Korea

Resume : The electrification is an essential phenomena for triboelectric nanogenerator (TENG). The electrification is interfacial charge transfer between two triboelectric materials. The amount of electrification can be affected by temperature, relative humidity, materials, and surface morphology. In the material case, the material characteristics such electron affinity, surface potential, work function, and band gap can affect the electrification. To enhance the material characteristics, researchers has utilized the chemical surface treatment such ionic gas injection and specific ion doping. In this study, we investigated the effect of interface engineering through atomic layer deposition (ALD). We prepared bare aluminum (Al) substrate as electrode for TENG device. The polytetrafluoroethylene (PTFE) was used for negatively charged material without nano/micro structure on the surface to avoid additional effect from PTFE. Finally, the positively charged material was prepared with the ruthenium (Ru), ruthenium oxide (RuO_2), and platinum (Pt) deposited on counter electrode with different thickness. The piezoresponse force microscopy (PFM) was utilized to mapping the surface potential of Ru, RuO_2, and Pt. We expected that our result provide fundamental design information for TENG.

C.P1.7
17:30
Authors : Heejae Hwang1, Dukhyun Choi1,2
Affiliations : 1 Department of Mechanical Engineering, College of Engineering, Kyung Hee University, 1732, Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, Republic of Korea ; 2 Industrial Liaison Research Institute, Kyung Hee University, 1732, Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, Republic of Korea

Resume : Harvesting energy from our living environment is an effective approach for sustainable, maintenance-free, and green power source for wireless, portable, or implanted electronics. As moving into a ubiquitous society, the demand for power source that substitute the conventional batteries have been increased for semi-permanent operation. Triboelectric nanogenerator(TENG) is one of the solution. To apply TENG to real life, the devices need to satisfy two conditions. First, the energy generation should be stable in harsh environments, such as in high humidity and pressure. Second, the shape of generator should be adaptable to various mechanical energy source such as wind, vibration, human motions and others. The most of previous TENG devices based on vertical contact-separation mode comprise two plate and spacer, roughly. The limited shape of TENG could restrict applications to narrow range. In this study, we focused on triboelectric nanogenerators that can harvest in various situation and harsh environments in order to overcome the weakness of TENG. We fabricated milti-shape sponge type TENG from Al micro-particles to utilize diverse mechanical energy source in daily life and avoid from surrounding condition, such as humidity and dust. Futhermore, the sponge like structure has an advantage in durability under relatively high pressure. We expect that our results increase the availability of TENGs in real life.

C.P1.8
17:30
Authors : Songhwa Chae1, Kwun-Bum Chung2, Dukhyun Choi1,3
Affiliations : 1. Department of Mechanical Engineering, College of Engineering, Kyung Hee University, 1732, Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, Republic of Korea 2. Division of Physics and Semiconductor Science, Dongguk University, 30, Pildong-ro 1-gil, Jung-gu, Seoul, 04620, Republic of Korea 3.Industrial Liaison Research Institute, College of Engineering, Kyung Hee University, 1732, De-ogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, Republic of Korea

Resume : Anodic Aluminum Oxide (AAO) has unique properties characterized by its ordered honeycomb structure that has excellent uniformity in diameter and spacing of the nanopores. AAO templates have received considerable attention for fabrication of nanotubes and nanowires due to characteristics such as highly controllable pore diameter and periodicity. Usually, AAO is fabricated under completely static conditions for uniform development of the nanostructures. In this study, we report AAO fabrication through dynamically controlled two-step anodization process, on pure aluminum substrate (99.999%). The first-anodization step was maintained as static, similar to conventional process. In the second-step anodization step we used a novel dynamic method whereby the aluminum substrate is moved vertically upwards towards the mouth of the container at a constant and controlled pace. This process results in uniformly varying nanopore fabrication. In order to compare the properties of the conventionally fabricated AAO with dynamically fabricated AAO, we performed FE-SEM imaging. Additionally, we deposited gold nano-particles on the dynamically fabricated AAO template by thermal evaporation. This was done to investigate the optical properties of the AAO template by UV-Visible spectrometry. We expect that our novel dynamic AAO fabrication technique will help in easier fabrication of AAO templates for plasmonic applications.

C.P1.9
17:30
Authors : Grzegorz Matyszczak (1), Karolina Pietak (1), Daniel Jastrzebski (1), Michal Wrzecionek (1), Dorota Brzuska-Kamoda (1), Piotr Pietrzak (1), Slawomir Podsiadlo (1)
Affiliations : (1) Faculty of Chemistry, Warsaw University of Technology; Noakowskiego 3, 00-664 Warsaw, Poland

Resume : A growing interest in two-dimensional (2D) layered nanostructures has been observed due to their potential future applications in nanoelectronics and renewable energy harvesting. Manganese(II) thiostannate shows particularly appealing features, which combined with their environmental harmlessness and low-cost production makes them promising materials for use in photovoltaics. In this study, nanolayers of MnSnS3 – prepared electrochemically in aqueous solutions – have been investigated. The obtained materials have been characterized with X-ray diffraction, Raman scattering spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy and cyclic voltammetry.

C.P1.10
17:30
Authors : S. Kratro
Affiliations : Department Electrophysics, Faculty of Radiophysics,Electronics and Computer Systems, Taras Shevchenko National University of Kyiv

Resume : The fulleroly Cmn derivatives were prepared by light illumination and ozonolysis of C70 gel solution. Experimental investigation was carried by UV-vis, IR, Raman spectroscopy, XPS and AFM. The structure of Cmn derivatives in gel solution (aggregates with hydrated shell) was studied. I present results from initial screening of the candidates based on informatics quantitative structure - property relationships, their comparison with results from density functional theory calculations about the effect of donor-acceptor architectures on the efficiency of the photovoltaic device. The comparison of spectral features for Cmn derivatives with the data for the adsorbed layers allowed to detect a series of Cmn hydroxyl group of derivatives.

C.P1.11
17:30
Authors : A.P. Bakhtinov (1), V.N. Vodopyanov (1), Z.R. Kudrynskyi (2), Z.D. Kovalyuk (1), V.V. Netyaga (1), V.L. Karbivskyi (3), O.S. Lytvyn (4)
Affiliations : (1) - Frantsevich Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, Chernivtsi Department, str. Iryny Vilde 5, 58001 Chernivtsi, Ukraine; (2) - School of Physics and Astronomy, The University of Nottingham, Nottingham, NG7 2RD, UK; (3) - Kurdyumov Institute of Metallophysics, National Academy of Sciences of Ukraine, bulv. Akademika Vernadskogo, 03680 Kyiv, Ukraine; (4) - Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, pr. Nauky 4, 03028 Kyiv, Ukraine

Resume : The growth morphology, composition, structure and electrical properties of nanocomposite structures based on ionic salts MeNO3 (M=K,Rb) and p-GaSe (n-InSe) layered semiconductors were studied by means of atomic force microscopy, X−ray diffractometry, photoelectron spectroscopy and impedance spectroscopy. Nanocomposite materials were prepared by inserting ionic salts from melt between layers of the layered crystals and sintering ionic salt/nanocrystalline GaSe (InSe) powder mixtures. At high temperatures (>650K) the molten salt molecules, which are present in van der Waals interlayer gaps (0.38nm) of these crystals, decompose into MeNO2 and O2 ions. The formation of nanocomposite structures may occur with oxidation and destruction of GaSe (InSe) layers. We used this method to exfoliate III−VI layered crystal multilayers for production of nanostructures consisting of III-VI semiconductor 2D nanosheets, nanoscale Ga(In) oxides and ionic salt inclusions. The structures provide a new example of nanocomposites in which ionic conductivity along layers occurs via interfaces between the oxidized (0001)surfaces of the layered crystals and ionic salt. It was found that conductivity of these composites depends on morphology, chemical composition and interfacial structure of the nanostructures. A significant decrease in the impedance magnitude of the nanocomposite structures illuminated with different light wavelengths in the region of fundamental optical absorption of InSe was observed.

C.P1.12
17:30
Authors : Aleksandr S. Doroshkevich*1,2, Artem V. Shylo2, Andriy Lyubchyк3, Kholmizo Т. Kholmurodov1, Tetyana Yu. Zelenyak4,Victor I. Bodnarchuk1, Tetyana E. Konstantinova2, Valentin.V.Sadilov5, Susanna A. Synyakina2 Akhmed H. Islamov1 and Mihai L. Craus1
Affiliations : 1Joint Institute for Nuclear Research, 141980, Joliot-Curie str., 6, Dubna, Russia 2Donetsk Institute for Physics and Engineering NASU, 03083, Nauki ave, 46, Kyiv, Ukraine 3 i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP/UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal, 4Dubna International University for Nature, Society and Man, 141980, Moscow region, Dubna, st. Universitetskay, 19 5Lomonosov Moscow State University, Faculty of Physics, Russia, 119991, Moscow, GSP-1, 1-2 Leninskiye Gory * Corresponding author e-mail: doroh@jinr.ru

Resume : Nanostructured systems - this is an extremely thermodynamic nonequilibrium structure. At present, they are widely used in electronics and other fields of the national economy as a functional environment of different devices. Their physical responses to external stimulus, is unique due to their thermodynamic critical condition. Nanostructured systems are extremely thermodynamically unstable structures. Nowadays they are widely used in electronics and many other fields as a functional medium for wide variety of devices. Their physical responses to external stimuli are unique due to their thermodynamic critical condition. Typically, physical influence of external stimuli such as an electric field, pressure or thermal effect on heterogeneous nanostructured systems induce activation of certain physical/chemical processes at the phases interface. Namely, redistribution of the free energy between the volume of the dispersed phase (nanoparctile) and a dispersion medium (surrounding atmosphere) followed by change in the charge and adsorption equilibriums. In simplest case it is widely known nanoionics capacitor, where the application of an external electric field to the particles of disperse phase with an electronic conductivity leads to the adsorption of ions from disperse medium (electrolyte) on phases interface. In this case external energy is localized in a thin layer between the surfaces of the disperse phase (electrode) and electrostatically associated with them electrolyte ions. Thus, the variation of charge balance of thermodynamically unstable surface of nanodispersed system by external electric field led to change of adsorption balance at phases interface. Consequently, such system accumulates external energy in the form of changes of spatial configuration of structural elements (adsorbed ions). It is known that the opposite process leads to exothermic effect. Many oxide powders are excellent sorbents. Consequently, they are releases energy when placed in a humid atmosphere. This property of oxide systems is widely used for the development of a new building "smart" - materials with space-conditioning functions within the change of the day time. In this study, based on example of ZrO2 nanopowders (specific surface area SBET≈140 m2/g) with high adsorption capacity towards water vapor was shown that exothermic release of energy of water vapor with surface of oxides nanoparticles can be efficiently transformed in electric form. The work was supported through the project H2020/MSCA/RISE/HUNTER/691010

C.P1.13
17:30
Authors : Yuki Maruyama, Yuki Yanase, Tomoaki Watanabe
Affiliations : Meiji University

Resume : Recently, rare earth doped SrAlSiN3 phosphor for white LED has attracted attention because of a broad excitation and emission band. Moreover, SrAlSiN3 exhibits an excellent thermal stability and high chemical stability. In generally, rare earth doped SrAlSiN3 have been synthesized at 2173 K under high pressure nitrogen atmosphere (190 MPa) by a conventional solid state reaction. In this study, we successfully synthesized SrAlSiN3:Ce3+ at 1073 K under supercritical ammonia (100 MPa) using the ammonothermal method. The products prepared using the ammonothermal method had a plate-like crystal morphology. Ce3+, Na+ co-doped product exhibited a broad emission band that was centered at approximately 550 nm by irradiation of 460 nm blue light. Na+ was used as the charge compensator. Na+ has important role for charge compensator of Sr2+ and Ce3+. Furthermore, we investigated the effects of mineralizers on the products synthesized using the ammonothermal method. The results of X-ray diffraction analysis indicated that the optimal mineralizer for SrAlSiN3:Ce3+ synthesis was Sr + NaNH2 because the sample treated at this mineralizer exhibited the highest diffraction intensity and the smallest half-value width. The product prepared using Sr + NaNH2 as a mineralizer exhibited the highest emission intensity.

C.P1.14
17:30
Authors : Matthew Zervos ? , Eugenia Vasile ?, Eugeniu Vasile ? and Andreas Othonos *
Affiliations : ?Matthew Zervos, Nanostructured Materials and Devices Laboratory, School Of Engineering, University of Cyprus, P.O.Box 20537, Nicosia, 1678, Cyprus ; ?Eugenia Vasile and Eugeniu Vasile, Politehnica University of Bucharest, 313 Splaiul Independentei, Bucharest, Romania * Andreas Othonos, Laboratory of Ultrafast Science, Department of Physics, University of Cyprus, P.O.Box 20537, Nicosia, 1678, Cyprus.

Resume : Metal oxide semiconductor nanowires , such as n-type ZnO , SnO2 , In2O3 and Sn doped In2O3 nanowires, have been investigated extensively in the past, and are important for the fabrication of electronic and optoelectronic nanoscale devices, such as nanowire solar cells, sensors, photodetectors etc . On the other hand, p-type chalcogenide semiconductors such as Cu2S and PbS have been used in conjunction with metal oxides for the realization of different types of solar cells. One of the main advantages of PbS over Cu2S is that it has a lower energy band gap so it absorbs infra red photons that are transmitted through wider band gap oxides thereby increasing the overall efficiency of solar cells. In this talk I will present recent work on the synthesis , structural, electrical and optical properties of core-shell PbS/In2O3 nanowires which have been used in a quantum dot sensitized solar cell. We show that PbS/In2O3 nanowires may act as efficient, highly conductive junctions in such solar cells that also absorb in the near infra red as shown by photo luminescence measurements. More importantly the properties of these nanowires such as the band bending and charge distribution have been determined within the effective mass approximation taking into account the effective mass, dielectric constant differences and Fermi level pinning at the surface of the PbS shell which is constitutive in understanding the operation of different types of solar cells.

C.P1.15
17:30
Authors : Davide Barreca,1 Giorgio Carraro,2 Alberto Gasparotto,2 Chiara Maccato,2 Elza Bontempi3
Affiliations : 1 CNR-ICMATE and INSTM, Department of Chemistry, Padova University, 35131 Padova, Italy. 2 Department of Chemistry, Padova University and INSTM, 35131 Padova, Italy. 3 Chemistry for Technologies Laboratory, Brescia University and INSTM, Brescia, Italy.

Resume : The increasing attention devoted to hematite (α-Fe2O3) has been fuelled by its potential end-uses in a variety of technological fields, encompassing magnetism, biomedicine, photocatalysis, and solar energy generation. Nevertheless, the controlled preparation of α-Fe2O3 nanosystems and the detailed understanding of their nucleation/growth processes remain an open challenge still far from being completely satisfied. In this regard, the present work is devoted to the Plasma-Assisted Chemical Vapor Deposition (PA-CVD) of α-Fe2O3 nanosystems on Si(100) and SiO2 substrates starting from Fe(dpm)3 (Hdpm = 2,2,6,6-tetramethyl-3,5-heptanedione).1,2 The results obtained by a multi-technique chemico-physical characterization highlight the obtainment of single-phase α-Fe2O3 nanostructures already at temperatures close to the room one. Remarkably, the system nano-organization could be tailored from oriented nanoblade arrays to polycrystalline nanocolumns with enhanced light absorption upon increasing the deposition temperature. Overall, the present results candidate the proposed PA-CVD route as a versatile and amenable approach to hematite-based nano-architectures for a multitude of functional applications. 1 D. Barreca et al., Chem. Vap. Deposition, 2015, 21, 294. 2 D. Barreca et al., Phys. Chem. Chem. Phys., 2015, 17, 11174.

C.P1.16
17:30
Authors : Jin Yeong Na, Hwa Sung Lee, Yeong Don Park
Affiliations : Jin Yeong Na, Yeong Don Park; Department of Energy and Chemical Engineering, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Korea Hwa Sung Lee; Department of Chemical & Biological Engineering, Hanbat National University, 125, Dongseodaero, Yuseong-gu, Daejeon 34158, Korea

Resume : The efficiency of charge transport in organic electronics is expected to improve with better structural order and for conjugated polymers with stronger pi-pi interactions. However, the charge-carrier mobilities of solution-processed conjugated polymer films are generally limited by the hopping process between polymer chains in disordered regions. Further, unlike the solvent-dropping casting, typical thin film deposition methods such as spin-coating, which can be used to produce large-scale homogeneous films, cannot be used to produce molecularly ordered structures because of the fast solvent evaporation rate during film formation. In this study with the aim of enhancing the charge transport of polythiophene by promoting molecular ordering, we have developed a casting method via spin-coating time control. By manipulating the spinning time, it is possible to regulate the solvent evaporation rate of solution, which in turn improved the crystallinity of polythiophene thin films. With the short spinning time, the resulting polythiophene thin film adopt a highly ordered nanowire structures with a field-effect mobility dramatically improved by a factor of approximately 10 depending on the spinning time. By combining the advantages of the conventional spin-casting and drop-casting methods, we were able to produce semiconducting polymer thin film with high crystallinity and uniformity.

C.P1.17
17:30
Authors : Robert Szczęsny (1), Edward Szłyk (1), Duncan H. Gregory (2)
Affiliations : (1) Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Poland; (2) WestCHEM, School of Chemistry, University of Glasgow, Glasgow, UK

Resume : CuO, ZnO and Cu3N have been investigated for catalysis, sensing and optoelectronics. [1-3] It is known that the oxide and nitride layers can be obtained by physical e.g. sputtering processes, pulsed laser deposition technique or by chemical methods such as, microemulsion, hydrothermal, sol-gel and precipitation followed by the deposition of nanoparticles suspensions using wet coating methods. The use of spin-coating offers the opportunity for facile fabrication of thin films containing uniformly dispersed nanoparticles onto the substrates even for large areas, and allows to produce a wide variety of composite materials in mild conditions. In this work, Cu/Zn hydroxy carbonate precursors were utilized to prepare CuO/ZnO and Cu3N/ZnO nanocomposite NPs, and films on silicon substrate. Morphological evaluation by TEM and SEM measurements indicated that the particles are spherical in shape with diameters of 70-200 nm. Moreover, NPs have been characterized by TG, IR, Raman and XRD. The layers were obtained from ethanol suspension at rotation speeds of 3000-5000 rpm. The total thickness of films does not exceed 500 nm. Upon thermal treatment in air and NH3 atmosphere precursor transformed into oxide and oxide–nitride materials. REFERENCES [1]. R. Szczęsny, E. Szłyk, M. A. Wiśniewski, T. K. A. Hoang, D. H. Gregory, J. Mater. Chem. C, 2016, DOI: 10.1039/C6TC00493H. [2]. X. Zhao, P. Wang, B. Li, Chem. Commun., 2010,46, 676. [3]. J. Kim, W. Kim, K. Yong, J. Phys. Chem. C, 116 (29) (2012), 15682. ACKNOWLEDGEMENTS This work was supported by The Polish National Science Center (NCN) (grant no. 2013/09/B/ST5/03509).

C.P1.18
17:30
Authors : A.D.Yapryntsev, P.A.Tribunskaya, A.K.Podlesnyy, A.E.Baranchikov, V.K.Ivanov
Affiliations : Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia; Lomonosov Moscow State University, Leninskie Gory, building 1-3, Moscow, 119991, Russia; Lomonosov Moscow State University, Leninskie Gory, building 1-3, Moscow, 119991, Russia; Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia; Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia

Resume : The family of inorganic anion-exchangeable materials is currently quite limited and until recently it included only one type of such compounds, namely layered double hydroxides. In 2006, a new type of inorganic layered materials based on rare-earth hydroxides have been discovered. These layered rare-earth hydroxides (LRH) have attracted growing interest due to the possibility to combine properties of rare-earth elements (optical, catalytic and magnetic) with flexibility of anion-exchangeable host. Synthesis of these materials encountered some difficulties including long duration of synthesis due to structural disordering inherent to LRHs. Anion exchange reactions with LRHs are also kinetically limited due to high charge density of metal-hydroxide layers. In this work, we have proposed novel synthetic procedure based on microwave-assisted hydrothermal crystallization of LRHs in the presence of hexamethylenetetramine. The method we proposed allowed synthesizing highly crystalline layered yttrium, gadolinium, terbium, and europium hydroxides as well as corresponding solid solutions with high yields. Using both anion-exchange reactions and one-pot synthesis at ambient and hydrothermal conditions we have obtained LRH derivatives with different types of organic anions intercalated in the host, including aminoacids, sulfate and sulfonic fatty acids, aromatic carboxylates, etc. The composition and structure of LRHs and their derivatives were confirmed by PXRD, TGA, CHN, FTIR analyses. Luminescent properties of terephthalate-intercalated LRHs are being under intense study now.

C.P1.19
17:30
Authors : V.A. Turchenko1,2, M.L.Craus1,3, A.S. Doroshkevich2, T.E. Konstantinova2
Affiliations : 1 Joint Institute for Nuclear Research, Dubna, Russia 2 Donetsk Institute of Physics and Technology named after O.O. Galkin, Ukraine 3 National Institute of R&D for Technical Physics, Iasi, Romania

Resume : Ceramic zirconium oxides (ZrO2) are an important material with an increasing range of applications. Zirconia ceramic components have excellent fracture toughness, very good wear resistance, high corrosion stability, low thermal conductivity and coefficient of thermal expansion in range of steel. Their functional properties characterize zirconia as a leading structure material for a dental medicine [1] and solid-oxide fuel-cell design [2] and catalytic technologies [3]. This material are drawn attention towards the remarkable structural properties: with increasing temperature structure of pure zirconia with monoclinic symmetry (P21/c) [4] transforms to tetragonal symmetry (P42 /nmc), by approximately 1180 °C [5] and then to fluorite structure with a cubic symmetry (Fm-3m) starting about 2370 °C with melting by 2716 °C. The alloying of pure ZrO2 with CeO2, or with lower valence oxides such as CaO, MgO, La2O3, Y2O3 or certain other metal oxides, it is possible to stabilize the tetragonal phase at room temperature. These metastable phases are analogous to those in pure zirconia but have dopant ions which substituted Zr4+ ions and a corresponding concentration of oxygen vacancies to retain charge neutrality. The main aim of the work is the determination of influence of Y and Ce ions on the features of crystal structure and microstructural parameters of zirconia ceramic. The substitution of the Zr with Y or Ce in zirconium oxides leads to a transition from the monoclinic to tetragonal structure. Ceramic samples doped with Y ions are inhomogeneous. The volume of unit cell increases as the concentration of Y ions is increased. In Ce doped zirconium oxides we observed a difference of the phase composition between the surface layer of the sample and the phase composition of the bulk samples. We attributed this difference to the various oxygen concentration in the surface layer and in the bulk sample. 1. Panadero, R.A.; Roman-Rodriguez, J. L.; Ferreiroa, A.; Sola-Ruiz, M. F.; Fons-Font, Journal of Clinical and Experimental Dentistry 2014,6, 66-73. 2. Badwal, S.P.S.; Giddey, S.; Munnings, C.; Kulkarni, A.; Journal of the Australian Ceramics Society 2014, 50, 23-37. 3. Mercer, P.D.L.; Van Ommen, J.G.; Doesburg, E.B.M.; Burgraff, A.J.; Ross, J.R.H. Applied catalysis 1991, 71, 363-391. 4. J. D. McCullough and K. N. Trueblood, Acta Crystallogr. 1959, 12, 507.

C.P1.20
17:30
Authors : Jie Zhang
Affiliations : Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, Xi’an Jiaotong University, Xi’an 710049, China

Resume : Carbon nanotubes (CNTs) and zinc oxide (ZnO) are popular candidates as modifiers to optimize composites, because of their high strength, distinctive electrical, optical properties and high sensitivities towards gas, humidity and so on. In this report, we deposited CNTs and ZnO onto electrically insulating glass fiber surfaces by electrophoretic deposition and atomic layer deposition methods, respectively. Firstly, we found that the interfacial shear strength of single fiber composites has been singnificantly improved by nanolayers. Importantly, a critical thickness of nanolayer, corresponding to the maximum interfacial strength has been firstly experimentally obtained. Subsequently, we utilized single modified fibers to produce the multifunctional sensors. The modified single fiber by CNTs demonstrated a high sensitivity to the stress/strain through the simultaneous measurement of the electrical resistance under tensile loading. The strain sensitivity factor, GF, of CNTs-glass fibre is much higher than those of conventional metallic strain gages with geometrical piezoresistive effect, which displays a potential as in-situ micro sensor in materials. At the same time, the CNTs-glass fibre was used as an in-situ chemical/physical sensor to characterize the processes of curing or crystallization of polymers through monitoring the low mobility of charge carriers in insulative materials. The glass transition was also interpreted by the resistance measurement.

C.P1.21
17:30
Authors : Zai-xing Yang[1][2][3], SenPo Yip[1][2][3], Dapan Li[1][3], Ning Han[4], Guofa Dong[1][3], Xiaoguang Liang[1][3], Lei Shu[1], Tak Fu Hung[1], Xiaoliang Mo[5], and Johnny C. Ho[1][2][3]
Affiliations : [1]Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon 999077, Hong Kong; [2]State Key Laboratory of Millimeter Waves, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon 999077, Hong Kong; [3]Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, P. R. China; [4]State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, P. R. China; [5]Department of Materials Science, 220 Handan Road, Fudan University, Shanghai 200433, P. R. China

Resume : The diameter-dependent properties and hole mobility limit of GaSb nanowires (NWs), an intriguing candidate for next generation high performance p-type transistors, are difficult to address due to the difficulty in achieving thin and uniform nanowires. In this study, uniform and high quality GaSb NWs are successfully prepared by surfactant-assisted chemical vapor deposition and utilized to study their diameter dependent growth orientation and hole mobility. The role of the sulfur surfactant has also been elucidated that it stabilize the high energy (111) and (311) NW sidewalls efficiently and hence thin NWs (<40nm in diameter) grow along <211> and <110> direction while thick NWs(>40nm in diameter) grow along the most energy-favorable close-packed planes with the orientation of <111>. More importantly, for the first time, peak hole mobility of ∼400 cm2 V s-1 for the diameter of 48 nm, approaching the theoretical limit under the hole concentration of ∼2.2x10^18 cm3, has been achieved by controlling the sulfur passivation, growth orientation and surface roughness. All these show the promising properties of passivated and well controlled GaSb nanowires for future technological application.

C.P1.22
17:30
Authors : Ho-Yuen Cheung[1], SenPo Yip[2][3], Ning Han[4], Goufa Dong,[2] Ming Fang,[2] Zai-xing Yang[2][3], Fengyun Wang[5], Hao Lin[2], Chun-Yuen Wong[1][3], Johnny C. Ho[2][3]
Affiliations : [1]Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong; [2]Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong; [3]State Key Laboratory of Millimeter Waves, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong; [4] State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, P.R. China; [5] Cultivation Base for State Key Laboratory, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, P.R. China

Resume : Unstable native oxide of InAs nanowires produces large amount of surface states leading to depletion mode operation with degraded electron mobility for field-effect transistor applications. In this work, we employ various substituted aromatic thiolate (ArS-)-based molecular monolayers for the surface modification of InAs nanowires (i.e., device channels) by simple wet chemistry. Besides the electron mobility and the current on-off ratio increase, the device threshold voltage (VTh) can also be modulated by changing the para-substituent of the surface modifier such that the molecule bearing electron-withdrawing groups would significantly result in more positive VTh change for the enhancement mode device operation, and the effect has been quantified by theoretical calculations (DFT). These findings demonstrate the efficient modulation of the InAs nanowires' electronic transport properties via ArS--based molecular monolayers, which shows the technological potency of such surface treatment for nano-electronic device fabrication and circuit integration in future.

C.P1.23
17:30
Authors : Juwon Lee, Sangyeon Pak, Jung Inn Sohn, SeungNam Cha, Jong Min Kim
Affiliations : University of Oxford; University of Cambridge

Resume : Monolayer transition metal dichalcogenides (TMDCs) are considered to be promising candidates for flexible and transparent optoelectronics applications due to their direct bandgap in the visible range and strong light-matter interactions. However, the growth of large-sized TMDC monolayer crystals is significantly challenging. Here, we report a growth method for large-scale MoS2 crystals up to 300 um via solution-processed precursor deposition. To realize the growth of a large-sized monolayer, it is important to decrease the nucleation density on the substrates. Our simple method provides a way of depositing an extremely small amount of Mo precursors (< 0.05 mg) with a uniform distribution. Although the growth with a large amount of Mo precursors (> 10 mg) yielded small-sized crystals on specific regions of the substrates, the large monolayer crystals and films have covered the whole area of the substrates (2 x 2 cm) with our growth method. The simple and scalable growth methods, controlling the amount of precursors, can open up new opportunities for the mass production of TMDC monolayers.

C.P1.24
17:30
Authors : Mariusz Szkoda(1), Anna Lisowska-Oleksiak(1), Jakub Rysz(2), Jacek Ryl(3), Katarzyna Siuzdak(4)
Affiliations : (1) Faculty of Chemistry, Gdansk University of Technology, Narutowicza 11/12, 80-233, Gdansk, Poland; (2) Faculty of Physics, Astronomy, and Applied Computer Science, Jagiellonian University in Kraków, ul. Gołębia 24 , 31-007 Kraków, Poland; (3) Department of Electrochemistry, Corrosion and Materials Engineering, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland (4) Center for Plasma and Laser Engineering, The Szewalski Institute of Fluid Flow Machinery, ul. Fiszera 14, 80-231 Gdansk, Poland

Resume : Hybrid materials based on organic conducting polymers (CP) and inorganic ordered nanostructures have been at the leading edge of research and development. A wide range of such composites has been obtain bringing together titnaia nanotubes (TiO2NT) as n-type element and poli(3,4-ethylenedioxythiophene), polyaniline or polypyrrole as p-element of the junction. These combinations exhibit attractive features in many applications from organic electronics to solar cells, energy storage and sensors. As an advanced form of organic-inorganic ordered heterojunction, we propose introduction of redox centres (Prussian blue analogues) inside the p-n hybrid that plays important role in electrochemical and photoelectrochemical behaviour. As n element the ordered titania arrays produced via anodization were used whereas poli(3,4-ethylenedioxythiophene) containing different transition metal hexacyanoferrates (Mehcf) acted as a p-element. Here, we focus on detailed studies using SIMS and XPS techniques that allow to investigate the penetration of metal oxide nanostructure by organic matrix and redox centres as well as the oxidation state of introduced species, respectively. Obtained results show that proposed preparation method of TiO2NT/pEDOT:Mehcf heterojuntion lead to efficient deposition of CP together with redox centres along the tubular layer. The financial support of the Polish National Science Centre: grant No. 2012/07/D/ST5/02269 is gratefully acknowledged.

C.P1.25
17:30
Authors : Hadi Sedaghat Pisheh (a); Negar Gheshlaghi (a); Hilmi Ünlü (a,b)
Affiliations : (a) Nanscience and Nanoengineering Programme, Institute of Science and Technology İstanbul Technical University, Maslak Istanbul 34469 TURKEY (b) Department of Physics, Faculty of Science and Letters İstanbul Technical University, Maslak Istanbul 34469 TURKEY

Resume : Semiconductor nanocrystals (known as quantum dots (QDs)) have been the subject of great scientific and technological interest due to their potential optical applications that include photovoltaics, solar cells, light emitting diodes (LEDs) and lasers. CdSe based quantum dots can be a good candidate to use as an intermediate bandgap layer in solar cells. QD solar cells have the potential to increase efficiency of solar photon conversion by generating and collecting additional electron–hole pairs. In this work, we synthesized CdSe based CdSe/Cdx Zn1-xS (0≤x≤1) core/ternary shell nanocryctals. The synthesized nanocrystals were characterized using the x-ray diffraction (XRD) and TEM for structural properties along with UV absorption, fluorescence and dielectric for optical properties. Compressive force applied on CdSe (core) by CdxZn1-xS shell led in band gap increase and core size decrease relevant with alloy composition and strain amount. The lattice mismatch induced interface strain between core and shell obtained from continuum elastic theory (CET) and applied in effective mass approximation (EMA) to calculate corresponding capped core diameter. The results compared with bare CdSe size from TEM to evaluate squeeze amount in core size after compressive shell deposition. İnduced interfacial strain amount found to be proportional with Zn-S bonds in alloy composition which induce higher compressive strain in core region. The relaxation peaks in dissipation factor (tan δ) found to shift to higher frequencies as composition of Zn-S bond increases in shell material.

C.P1.26
17:30
Authors : E.Venkata Ramana1*, A.Mahajan2, N.M.Ferreira1, M.P.F.Graça1, and M.A.Valente1
Affiliations : 1 I3N-Aveiro, Department of Physics, University of Aveiro, Aveiro-3810 193, Portugal. 2 School of Engineering and Material Science, Queen Mary University of London, London, E1 4NS, UK

Resume : Piezoelectric materials have widely been used to fabricate actuators, sensors and transducers. In these applications traditionally used materials are lead-based (such as lead zirconate titanate, PZT), which have stronger piezoelectric properties, (d33 ∼300–550 pC/N). However, in view of toxicity of lead during processing, there´s an increasing demand to replace lead based oxides with lead-free ones. This lead to rigorous studies on variety of Pb-free oxides with improved piezoelectric properties such as (Na, Bi)TiO3-BaTiO3, (K, Na)NbO3, SiO2, AlN, LiNbO3, Aurivillius family of oxides. Liu and Ren recently observed a large piezoelectric coefficient, d33~600 pC/ N in (1-x)Ba(Ti0.8Zr0.2O3)-x(Ba0.7Ca0.3)TiO3 (BZT–BCT) solid solutions with a morphotropic phase boundary (MPB) at x = 0.5, a value larger than that of soft PZT. The phase diagram of this compound is similar to that of PZT in a way that it consists of paraelectric cubic (C) and two ferroelectric rhombohedral (R) and tetragonal (T) phases. High-quality piezoelectric BZT-BCT films with dense and homogenous microstructure were fabricated using electrophoretic deposition method on platinum foil. The thick films post growth were annealed using the laser with power in the range 25 – 75 W for 5 to 30 min using a continuous CO2 Spectron SLC laser (λ=10.6 μm; 200 W). The films with a thickness of 10 μm exhibited high relative permittivity of 2400, low dielectric loss of 1.3% (at 10 kHz), and slim ferroelectric hysteresis loops. The piezoresponse force microscopic measurements displayed domain reversal characteristics. The physical properties are studied as a function of laser annealing parameters and the results are presented.

C.P1.27
17:30
Authors : Giorgio Carraro,1 Davide Barreca,2 Michael E.A. Warwick,1 Kimmo Kaunisto,3 Alberto Gasparotto,1 Chiara Maccato,1 Valentina Gombac,4 Cinzia Sada,5 Stuart Turner,6 Gustaaf Van Tendeloo,6 Paolo Fornasiero4
Affiliations : 1 Department of Chemistry, Padova University and INSTM, 35131 Padova, Italy; 2 CNR-ICMATE and INSTM, Department of Chemistry, Padova University, Padova, Italy; 3 Department of Chemistry and Bioengineering, Tampere University of Technology, 33101 Tampere, Finland; 4 Department of Chemical and Pharmaceutical Sciences, ICCOM-CNR Trieste Research Unit - INSTM Research Unit, Trieste University, 34127 Trieste, Italy; 5 Department of Physics and Astronomy, Padova University, 35131 Padova, Italy; 6 EMAT - University of Antwerp, 2020 Antwerpen, Belgium.

Resume : Thanks to their peculiar chemico-physical properties, metal oxide nanomaterials can be usefully exploited in a variety of photocatalytic processes, encompassing sunlight-assisted H2 generation and pollutant degradation for decontamination/disinfection processes.1,2 In this context, the development of Fe2O3-TiO2 nanocomposites is a valuable option for the production of photocatalysts with improved performances. In the present study, Fe2O3-TiO2 systems are prepared by a vapor phase route, consisting in the atomic layer deposition (ALD) of TiO2 layers with tuneable thickness onto Fe2O3 nanostructures produced by plasma enhanced-chemical vapor deposition (PE-CVD).1 The target materials are subjected to a structural, compositional, morphological and optical characterization, and their photocatalytic performances tested in the photodegradation of methyl orange aqueous solutions. The intimate contact between the two oxides is responsible for the appreciable activity improvement with respect to the single oxides upon both solar and Vis illumination, thanks to the improved charge carrier separation at the Fe2O3/TiO2 interface. Overall, the present results disclose interesting perspectives not only for real-world applications in wastewater treatment, but also for the development of photoelectrochemical cells aimed at H2O splitting triggered by solar light. 1 G. Carraro et al., CrystEngComm, 2015, 17, 6219. 2 G. Carraro et al., Adv. Mater. Interfaces, 2015, 2, 1500313.

C.P1.28
17:30
Authors : G. Carraro,1 C. Maccato,1 A. Gasparotto,1 D. Barreca,2 M. Walter,3,4 L. Mayrhofer,3,4 M. Moseler,3,4 R. Seraglia 2
Affiliations : 1 Department of Chemistry, Padova University and INSTM, 35131 Padova, Italy; 2 CNR-ICMATE and INSTM, Department of Chemistry, Padova University, 35131 Padova, Italy; 3 Fraunhofer Institute for Mechanics of Materials, 79108 Freiburg, Germany; 4 Freiburg Materials Research Center, Freiburg University, 79104 Freiburg, Germany.

Resume : Fe2O3-based materials have attracted a great attention thanks to their abundance, easy accessibility to different polymorphs and wide range of chemico-physical properties. In particular, the tailored control of their nano-organization has significantly boosted their functional applications, that include magnetic recording media, gas sensors, heterogeneous (photo)catalysts, and anodes in photoelectrochemical cells for H2O splitting.1,2 In this work, Fe(dpm)3 (Hdpm = 2,2,6,6-tetramethyl-3,5-heptanedione) has been exploited as molecular precursor for the PECVD (plasma enhanced chemical vapor deposition) of iron oxide nanosystems.3 A detailed investigation of Fe(dpm)3 structural, electronic, thermal and fragmentation behavior, enabled by a combined experimental and theoretical approach, highlighted its favorable features in view of PECVD applications. In fact, Fe(dpm)3 displayed a high stability to air/moisture, a single-step vaporization and a clean fragmentation pathway, representing key advantages for its use in PECVD. Growth experiments from Ar-O2 plasmas yielded α-Fe2O3 nanodeposits with high purity and controlled nano-structure. The possibility of obtaining crystalline Fe2O3 at temperatures as low as 100°C enables deposition even on thermally labile substrates, a key issue in view of technological applications. 1 ACS Appl. Mater. Interfaces, 2015, 7, 8667. 2 Thin Solid Films, 2014, 564, 121. 3 Phys. Chem. Chem. Phys., 2015, 17, 11174.

C.P1.29
17:30
Authors : Sangyeon Pak, Jung Inn Sohn, SeungNam Cha, Jong Min Kim
Affiliations : Sangyeon Pak - University of Oxford; Jung Inn Sohn - University of Oxford,; SeungNam Cha - University of Oxford; Jong Min Kim - University of Cambridge;

Resume : Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been recently considered as promising building blocks for next generation flexible and transparent optoelectronic devices due to their direct bandgap and atomically thin nature. In this regard, understanding their intrinsic properties and modulation and engineering their inherent characteristics are the main challenges for their optoelectronic applications. Therefore, finding effective methods to tune their electrical and optical properties and understanding their optical and vibrational properties can be promising approach to implement 2D crystals for optoelectronic devices. Here, we suggest employing self-assembly monolayer (SAM) method to modulate vibrational, optical and electrical properties of CVD-grown monolayer molybdenum disulfide (MoS2). By engineering their properties of monolayer MoS2 through surface treatment, its properties were largely changed, confirmed with Raman spectroscopy, photoluminescence spectroscopy, and threshold shifts in its back gate transistor.

C.P1.30
17:30
Authors : Siti Rahmah Aid (1), Umar Abdul Aziz (1), Nur Nadhirah Mohamad Rashid (1), Satoru Matsumoto (1), Anthony Edward Robert Centeno (1,2),Fang Xie (2), Hiroshi Ikenoue (3), Akira Suwa (3), David McPhail (4)
Affiliations : (1)Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia; (2)Imperial College London; (3)Kyushu University,Japan; (4)University of Texas at Dallas

Resume : Germanium (Ge) has recently received much attentions to replace silicon (Si) as a substrate for MOS-transistor due to its higher carrier mobility enables continuous improvement in LSI devices performance. Enhancing performance of MOS-transistor devices requires high-ratio of activated carrier within operating regime of pn junction. Nonetheless, fabrication of shallow pn junction remains challenging in Ge-based nMOS-transistor due to the severe ion-implantation damages introduced by n-type ions deactivate the carrier during subsequent thermal annealing process. Recently, co-implantation technique utilizing two dopant-ions different in size has just started to gain interest. Enhancement of carrier activation may be realized by introducing stress associated with atomic size into pn junction. Employing ultra-fast laser annealing will further lead to less dopant diffusion and improvement in carrier activation. This paper reports the formation of shallow n-type junction in Ge using co-implantation technique; followed by nanosecond laser annealing. Phosporus (P) with atomic radius of 98 pm were selected as a dopant, while tin (Sn) with atomic radius of 145 pm as non-dopant atoms for the co-implantation process. KrF excimer laser (wavelength: 248 nm, pulse duration: 50 ns) was selected for the subsequent thermal annealing process. Laser energy fluences of 300 and 500 mJ/cm2 were selected with laser shot number varied from 2 to 4 shots. A sample that was only implanted using single P-ions implantation was also prepared for comparison. The effect of co-implantation and laser fluence on dopant activation, diffusion and recrystallization of the amorphous Ge layer were investigated using various analytical tools. It is found that slight improvement is observed in the sheet resistance and crystallinity of co-implanted samples; with less diffusion at lower laser fluence. The shifting of Raman peak is observed which is considered due to the localized strain associated with different atoms size.

C.P1.31
17:30
Authors : Rizwan Wahab1*, Farheen Khan 2, Yogendra Kumar Mishra 3, I.H.Hwang 4, Hyung-Shik Shin 5, Javed Mussarat 1 and Abdulaziz A. Al-Khedhairy1,
Affiliations : 1. Zoology department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia 2. Department of Chemistry, Aligarh Muslim University, Aligarh 202002 U.P. India 3. Institute for Materials Science, Functional Nanomaterials University of Kiel, Kaiser Str. 2, 24143 Kiel, Germany. 4.Department of Animal Resources and Biotechnology, Chonbuk National University, Jeonju 561-756, Republic of Korea 5. Energy Materials & Surface Science Laboratory, Solar Energy Research Center, School of Chemical Engineering, Chonbuk National University, Jeonju 561-756, Republic of Korea

Resume : Quantum dots from different metal oxides have shown promising potentials in the direction their utilizations in the field of nanoelectronics and biomedical engineering etc. Among all, zinc oxide nanostructures, particularly 1D (nanorods/nanowires) and 0D (nanoparticles/ quantum dots) are probably the most studied nanomaterial candidates from metal oxide family for various applications. Due to the extremely biocompatible in nature, ZnO nanostructures find enormous application scope in biomedical medical engineering. Utilization of ZnO nanostructures for different biological studies, e.g., antimicrobial, antiviral, etc. has already shown their importance in this field, however in the direction of cancer, it is less explored. Understanding and treatment of cancer disease is one of the most challenging issue now-a-days in whole world (lot of people die due to this worldwide) and ZnO quantum dots (QDs) could play an important role in this direction and which has been explored in the present work. The present study demonstrates, simple and low temperature fabrication of ZnO QDs via solution route and have been used to treat the C2C12 cancer cells for investigating their anticancerious activity. The observations reveal that the treatments with QDs at dose dependent manner sensitize the cells. Detailed morphological, structural and luminescent properties of synthesized QDs have been investigated using different appropriate techniques. The viability of cells with QDs was analyzed via well-known MTT method. The morphology of cells was observed via confocal microscopy and it confirmed that with respect to increase in treatment time interval with QDs, the number of cancer cells decreased and control the growth significantly.

C.P1.32
17:30
Authors : Jong Kuk Lim, One-Sun Lee, Jae-Won Jang, Sarah Hurst Petrosko, George C. Schatz, and Chad A. Mirkin
Affiliations : Department of Chemistry, Chosun University, Gwangju, Korea; Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha, Qatar; Department of Physics, Pukyung National University, Busan, Korea; Department of Chemistry, Northwestern University, Evanston, Illinois, USA;

Resume : For the realization of molecular electronic devices, methods must be developed for creating molecular transport junctions (MTJs), tiny gaps between electrodes connected with molecules, in a straightforward and reproducible fashion. Here, we have demonstrated that MTJs can be fabricated by bringing segments of nanowires into contact via capillary forces. We further show that the combination of capillary force and van der Waals force can overcome the repulsive forces of electric double layer force and friction force when the total active length of each gold segment is below ~500 nm, and the radius of each gold segment is larger than ~180 nm. This method may become a widely adopted and convenient technique for preparing MTJs bridged with molecules, especially for the analysis of those moieties below 2 nm in length, which are challenging to fabricate via traditional MTJ preparation techniques.

C.P1.33
17:30
Authors : Mykola Pavlenko1,Igor Iatsunskyi2, Emerson Coy2, Mariusz Jancelewicz1, Grzegorz Nowaczyk1, Stefan Jurga1, Valentin Smyntyna1
Affiliations : 1. Odessa I.I. Mechnikov University, Odessa, Ukraine, str. Pastera,42,65-082; 2. NanoBioMedical Centre, Adam Mickiewicz University in Poznan, str.Umultowska, 85, 61-614;

Resume : The Au-TiO2 laminates, especially bilayered nanostructures, are considered to be an advanced material for catalysts, biosensor and electronic applications . It is expected these laminated structures posses enhanced photocatalytic properties and stability. In order to find the correlation between structural, optical and catalytic properties, the deep analysis of the morphology must be performed. The combined method based on the magnetron sputtering and atomic layer deposition (ALD) for bilayered laminates fabrication was applied. Laminates were produced on the Si and glass substrates utilizing magnetron spattering for Au layers with different thickness and ALD technique for TiO2 layers. The main structural parameters (layer thickness, phase of the layers, orientation etc.) were revealed by means of transmission electron microscopy (TEM). It is clearly seen the layered structures of fabricated samples. The average thickness of gold layers varied from 8 to 23 nm depending on the deposition time. The thickness of the TiO2 layer was fixed – 40 nm. In order to reveal the phase structure of the TiO2, Raman spectroscopy was used. It was found some enhanced Raman effects caused by the presence of the gold layers. It is shown the possible application of the produced Au-TiO2 laminates.

C.P1.34
17:30
Authors : Maryam Azadeh, Cyrus Zamani, Abolghasem Ataie
Affiliations : School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, P.O.Box: 11155-4563, Iran

Resume : Silicon in various forms has attracted considerable interest in many applications, such as electronics, photovoltaic, biomedicine and innovatively as anodes in lithium ion batteries. A facile and cost effective process to synthesize silicon-containing nanocomposite from rice husk-originated silica is introduced. Rice husk is mainly consists of silica which naturally exists in form of nanoparticles. To reduce SiO2 to elemental Si, Mg can be used as a reducing agent. In this work, obtaining Si is mainly based on a magnesiothermic reduction process of SiO2 resulted in formation of elemental Silicon, MgO and Mg2SiO4. The remaining powders consist mainly of silicon and Magnesium oxide and Magnesium Silicate. The synthesized Si nanocomposite, before any hydrometallurgical step can be used as anode in lithium ion batteries. This work focuses on Synthesis of Si-containing composite from rice husk and the electrical property of Si-MgO-Mg2SiO4 composite. Products in each step are characterized using X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) for phase analysis and morphological studies. XRD patterns confirmed the formation of amorphous silica beside the FE-SEM images representing the spherical silica particles. After reduction process, SEM micrographs indicated the formation of Si-based nanocomposite with 250-400 nm in size, compatible with X-ray pattern. The electrical response of the Si-based nanocomposite was measured to be of 6×108Ω•m.

C.P1.35
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Nanomaterials: synthesis and applications : -
09:00
Authors : Yogita Patil-Sen*, Tim Mercer, Gary Bond
Affiliations : Yogita Patil-Sen*, School of Physical Sciences and Computing, University of Central Lancashire, Preston PR1 2HE, United Kingdom; Tim Mercer, School of Physical Sciences and Computing, University of Central Lancashire, Preston PR1 2HE, United Kingdom; Gary Bond, School of Forensic and Applied Sciences

Resume : Multifunctional core-shell type hybrid nanoparticles such as those made of superparamagnetic iron oxide nanoparticles (SPIONs) coated with either silica, lipids or peptides are emerging as new class of nanomaterials for drug delivery and hyperthermia cancer therapy. Coating SPIONs with biocompatible materials and controlling their physico-chemical properties reduces the agglomeration of ultra-fine sized particles, thereby increasing their dispersibility and stability, while keeping their superparamagnetic properties intact. Coating also enhances the drug loading efficiency of the nanoparticles. The multifunctional nanoparticles can be targeted specifically to the cancer cell by applying external magnetic field which can then release the drug to the tumour cell by inducing local hyperthermia. Herein, we report the heating ability of bare SPIONs and core-shell type nanoparticles and test their efficacy as drug delivery carriers. The synthesis of nanoparticles was carried out using the procedure reported in the literature and the anticancer drug doxorubicin was encapsulated in the core-shell. The results suggest that the drug loading efficiency increased upon coating and drug release is much more controlled under the alternating magnetic field which indicates that core-shell type nanoparticles are promising drug delivery systems for magnetic hyperthermia based cancer therapy.

C.5.1
09:15
Authors : Cedric Spaas (a), Rüveyda Dok (b), Olivier Deschaume (a), Carmen Bartic (a), Sandra Nuyts (b), Chris Van Haesendonck (a)
Affiliations : a) Department of a Physics and Astronomy, KU Leuven, Belgium b) Department of Oncology, KU Leuven, Belgium

Resume : Antibody and polymer coated gold nanoparticles in the 15 and 30 nm core diameter range are presented as radiosensitizing agents in the treatment of the head and neck squamous cell carcinomas. The presented parameters and configuration of the functionalizing capping layer allow to control the solution stability, targeting functionality and overall toxicity of the nanocomplexes. The various dependencies and characterizations to obtain this organic interface layer on the inorganic core material are identified and eventually, by targeting the epidermal growth factor receptor on the cell surfaces with the proposed configurations, internalization of the nanoparticles in the cell is obtained. Next, evaluation of the cellular structure after delivery of low dose irradiations, and study of the various downward cell signalizations allow to understand the metastasis process behind this localized eradication of the malignant cells.

C.5.2
09:30
Authors : Justyna TOMASZEWSKA, Jakub MICHALSKI, Krzysztof Jan KURZYDŁOWSKI
Affiliations : Faculty of Materials Science and Engineering Warsaw University of Technology

Resume : Multiphase solid materials containing nano-scale components have become a subject of considerable interest due to benefits that they offer compared to single phase materials. Among these, hybrid nanocomposites composed of inorganic nanoparticles incorporated into a host material have attracted much attention as alternative sorption media for heavy metals removal. The synergistic effects of two components reduce limitations observed in more commonly used single phase granular media, such as excessive pressure drop in fixed bed columns and the risk of release of nanoparticles into the environment. In this study we present a novel concept of hybrid filters dedicated for water pre- and post-treatment, combining capacities of solid particles retention and arsenic (As) ions removal. Commercial deep bed filters composed of a polypropylene (PP) non-woven fabric with fibres of diameter sizes in the range of 0.2 – 30 µm have been modified with various allotropies of iron oxide nanoparticles. Obtained hybrid filters have shown an increase in filtering efficiency of the most penetrating particle size of c.a. 20 – 40% compared to unmodified filter. Preliminary adsorption tests demonstrated that such hybrid filters exhibit a high efficiency of removal of As to below required limits of 10 µg/L from a spring water with moderate As concentration.

C.10.6
09:45
Authors : Marco Bogar1, Giancarlo Cincotti2, Giulio Pipan1,Stefano Lai3, Piero Cosseddu3, Annalisa Bonfiglio3, Alessandro Fraleoni Morgera1-4-5, Beatrice Fraboni6, Andrea Ciavatti6, Laura Basirico6, Tobias Cramer6
Affiliations : 1Dept. of Engineering and Architecture, University of Trieste, Italy 2 Department of Physics, University of Trieste, Italy 3Department of Electrical and Electronic Engineering, University of Cagliari, Italy 4 CNR-NANO S3, Via Campi 213/A, Modena, Italy 5 Sincrotrone Trieste S.C.p.A., Italy, 6 Dept. of Physics, Univ. of Bologna, Viale Berti Pichat 6/2, 40100 Bologna, Italy

Resume : Organic semiconducting single crystals (OSSCs) have been studied during the last years because of their good electrical properties, which allow to fabricate transistors or direct x-ray detectors. Inkjet printing techniques can be used to print solutions from which OSSCs are grown. However, more understanding of the crystal growth process is needed to fruitfully exploit the inkjet printing technique for producing organic-electronics-based devices. Here we report on the use of different Self-Assembled Monolayers (SAMs), deposited via either drop casting or inkjet printing onto gold substrates, as a way to control the morphology of TIPS-Pentacene (a well know organic semiconductor) single crystals and their characteristics of electrical exchange with the electrodes. In particular, the morphology of TIPS crystals and their electrical characteristics are reviewed against the different types of SAMs applied to the electrodes. Considerations over the effect of the different SAMs on the morphology of the developed crystals are made, and criteria for choosing SAMs able to maximize the charge transport at the crystal/electrode interface are discussed.

C.5.4
10:00
Authors : A. Gómez-Núñez(1), T. Puig-Walz(1), C. López(2), M. Font-Bardia(3), M. Aguilar(4), A. Vilà(1)
Affiliations : (1)Departament d’Enginyeries: Electrònica, Universitat de Barcelona, Martí i Franquès 1, 08028-Barcelona, Spain. ; (2)Departament de Química Orgànica i Inorgànica, Universitat de Barcelona, Martí i Franquès 1, 08028-Barcelona, Spain. ; (3)Unitat DRX (CCiT-Universitat de Barcelona), Solé i Sabarís 1-3, 08028-Barcelona, Spain. ; (4)Departament de Cristal·lografía (Universitat de Barcelona), Martí i Franquès s/n, 08028-Barcelona, Spain.

Resume : One of the most prolific areas of current research is focused on the synthesis of Nanoscale Coordination Polymers NCPs. The selection of the metal ion and the ligand allow the design and synthesis of NCPs with specific properties (chemical or physical), catalytic and biological activities, applications in gas storage, separation processes, magnetic materials, homogeneous catalysis, as precursors of metal oxides and also as chemotherapeutic agents or in drug delivery. The characteristics of the Zn(II) ion and the fact that Zn(II) complexes with O-donor ligands usually have antibacterial activity, have triggered the development of novel multifunctional Zn(II)-NCPs. Moreover most of the homochiral Zn-NCPs known have polydentate organic ligands with N and O donor atoms but those derived from naturally occurring and nitrogen free compounds are scarce. Here we present several Zn-NCPs, isolated from Zn(II) acetate dihydrate, using cheap and easily controllable processes at room temperature, with their X-ray crystal structures and evidence of their homochiral nature. A comparative study of the influence of the organic multitopic ligands on their thermal stability and their conversion to pure ZnO is also reported. The new products are excellent candidates for their utility in different areas (printed electronics, catalysis…) or for their potential biological activity or uses (as carriers in drug delivery among others).

C.5.5
10:15
Authors : Cristina Bertoni,1,2, Pasquale Naclerio,3, Emanuele Viviani,4, Simone Dal Zilio,5, Alessandro Fraleoni-Morgera,3,6,7*
Affiliations : 1: Global Technology Centre (GTC), Electrolux Italia SpA, C.so Lino Zanussi 30, 33080 Porcia (PN), Italy 1: Global Technology Centre (GTC), Electrolux Italia SpA, C.so Lino Zanussi 30, 33080 Porcia (PN), Italy 2: Sensors And Innovation Laboratory (SAIL), Dept. of Engineering and Architecture, Univ. of Trieste, Trieste, Italy 3: FlexTronix Laboratory, Dept. of Engineering and Architecture, Univ. of Trieste, Trieste, Italy. 4: Artificial Perception Laboratory, Dept. of Engineering and Architecture, Univ. of Trieste, Trieste, Italy 5: IOM-TASC CNR, Basovizza (TS), Italy 6: Organic OptoElectronics Laboratory, Elettra Sincrotrone Trieste, Basovizza (TS), Italy 7: CNR Nano S3, Modena, Italy *email: afraleoni@units.it

Resume : A novel fast, low-cost and easy procedure to generate polymer-nanofibers was used to make P3HT nanofibers-based chemiresistors. The so-obtained device is sensitive to acetone gas concentrations as low as 3 ppm, with linear response up to 30 ppm. Additionally, these sensors showed very fast response times, with complete baseline recovery within 10 seconds from the signal maximum at each tested analyte concentration. Most notably, these performances are reproducibly achieved using different gas carriers, namely nitrogen and air, suggesting that the recorded response is little dependent from the gaseous environment in which the detector is operating.

C.5.6
10:30 Coffee break    
 
2D materials and interfaces : -
11:00
Authors : J.E. ten Elshof
Affiliations : MESA+ Institute for Nanotechnology, University of Twente, Enschede, the Netherlands

Resume : Soft lithography, a family of conformal contact processes using a patterned elastomer stamp, offer low cost high throughput alternatives for the patterning of functional ceramics and other inorganic materials. They have been receiving considerable interest due to their simplicity, scalability and mild processing conditions, which makes them compatible with many materials and substrates. This presentation highlights a number of soft lithographic fabrication tools that we developed to micropattern metal oxide films, nanoparticles, organically modified silicas and graphene on substrates such as Si and flexible plastics. Printing or molding successive layers to realize 3D stacks and patterns is also possible. All soft patterning methods use elastomeric molds and stamps with a (sub)micron-sized relief pattern. At very high resolution, the easy mechanical deformation of the protruding features of the elastomer becomes a limiting factor. It is possible to use stiffer, less deformable elastomers to pattern smaller features, but they exhibit poorer adhesion to the substrate, and tend to leave residue layers. We developed a couple of new approaches to deal with this limitation, thus allowing lateral resolutions down to 50 nm in some of our processes. The applicability of soft patterning will be illustrated, e.g. by 3D cathode materials for Li batteries, graphene micropatterns on PET plastics, and ZnO micropatterns as sacrificial templates for subsequent deposition of epitaxial (La,Sr)MnO3 by pulsed laser deposition.

C.6.1
11:30
Authors : James Semple, Gwenhivir Wyatt-Moon, Dimitra Georgiadou, Thomas D. Anthopoulos
Affiliations : Department of Physics and Centre for Plastic Electronics, Imperial College London, London SW7 2AZ, UK

Resume : There has been a great deal of interest in the patterning of nanogap electrodes in recent years, owing to their potential as enablers of technologies based on molecular electronics, plasmonics and spintronics. While conventional techniques can be used to pattern symmetric nanogap electrodes on the order of 10 nm or below, complex nanopatterning methodologies are required to obtain asymmetric nanogap electrodes, such as the molecular ruler technique [1], electrodeposition [2] or atomic layer lithography [3]. Such asymmetric nanogap electrodes are key for a variety of nanoelectronic devices including nanoscale organic light emitting diodes (nano-OLEDs), nanoscale photodiodes and nanoscale Schottky diodes [4]. However, the above patterning techniques suffer from low throughput and poor scaleability, particularly over large-area substrates. In the past, we have reported on adhesion lithography, an unparalleled large-area nanogap patterning technique [5]. The process involves the modification of surface energies using self-assembled monolayers and has allowed the patterning of sub-15 nm nanogaps. Herein, we present advances in the technique and frame them within the current state of the art in asymmetric nanogap electrode patterning. Specifically, we detail advances in minimising gap dimensions to below 10 nm, increasing gap fabrication yields to > 90 % and boosting the width of the nanogaps up to 1 m, to achieve aspect ratios in excess of 108. Furthermore, we expand the catalogue of metal electrode materials possible to employ to include Al, Au, Ag, Cr & Ni, and show that this unique technique is compatible with a variety of flexible polymeric substrates. Finally, the unique advantages of these structures will be outlined, with emphasis large-area solution processed electronic and optoelectronic devices. [1] S. Johnson, D. Evans, G. Davies, E. Linfield, C. Wälti, Nanotechnology 20 (2009) 155304 [2] M. Deshmukh, A. Prieto, Q. Gu, H. Park, Nano Lett. 3 (2003) 1383 [3] X. Chen X, H. R. Park, M. Pelton, X. Piao, N. Lindquist, H. Im, et al. Nature Communications. 4 (2013) 2361 [4] J. Semple, S. Rossbauer, C. Burgess, K. Zhao, L. Jagadamma, A. Amassian, M. McLachlan, T. D. Anthopoulos, Small 12 (2016) 1993–2000 [5] D. Beesley, J. Semple, L. Jagadamma, A. Amassian, M. A. McLachlan, T. D. Anthopoulos, J. de Mello Nature communications 5 (2014) 3933

C.6.2
11:50
Authors : Francesco Bruni(1), Mauro Sassi(1), Marcello Campione(2), Franco Meinardi(1), Luca Beverina(1), Natalie Stingelin(3), Sergio Brovelli(1)*
Affiliations : (1) Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, IT-20125 Milano, Italy; (2) Dipartimento di Scienze dell?Ambiente e del Territorio e di Scienze della Terra, Università degli Studi di Milano-Bicocca, Piazza della Scienza 1, 20126, Milano, Italy; (3) Department of Materials, Imperial College London, London SW7 2AZ, UK *sergio.brovelli@mater.unimib.it

Resume : Controlling the nano-scale structure and morphology of molecular thin films is a key aspect in plastic electronics, as it is typically associated with charge transport and exciton mobility. One promising strategy for tuning the supramolecular architecture of organic films is the post-deposition activation of latent hydrogen bonds between conjugated moieteis suitably functionalized with labile functionalities, whose thermal cleavage leads to the formation of stable, crystalline, molecular aggregates. This strategy has been used to produce high-mobility ambipolar organic field-effect transistors and, more recently, to enhance the performances of bulk-heterojunction solar cells. We demonstrate, for the first time, that latent hydrogen bonds between organic moieties can be activated also by light, which provides the thermal energy necessary for direct laser writing of crystalline semiconducting nanopatterns with diffraction limited resolution. Our molecule of choice is a solution-processable diketopyrrolopyrrole (DPP) derivative, which, in its pristine state forms non-conductive, amorphous films. Optical patterning results in highly resolved crystalline nanostructures of deprotected DPP molecules, as confirmed by side-by-side differential scanning calorimetry and GIWAXS analysis. Thin-film transistors based on pristine and photo-converted DPP reveal over 1000-fold increase in hole mobility, reaching 10-3cm2/Vs, which matches state-of-the-art hole transporting molecular materials.

C.6.3
12:10
Authors : C.A. Chavarin1, C. Strobel2, J. Kitzmann1, G. Lupina1, C. Wenger1, M. Albert2, J. W. Bartha2
Affiliations : 1 IHP, Im Technologiepark 25, Frankfurt an der Oder, Germany; 2 TU Dresden, Noethnitzer str. 64, Dresden, Germany

Resume : The use of graphene as the base electrode in bipolar transistors (GBT), have theoretically shown devices capable of working in the THz regime [1]. The electric current between emitter and collector electrode in GBTs would be controlled by the potential of the base electrode which is isolated by the band gap of two semiconductors. This concept is based on a vertical arrangement of graphene and the semiconductors. Here we use n-type amorphous silicon (a-Si:H) as semiconductor material to bring in contact with graphene. Therefore, a step-wise electrical and structural characterization of the a-Si:H/graphene interfaces is a requirement for the understanding and implementation of GBTs. For this purpose, we investigated the plasma-enhanced chemical vapor deposition of a-Si:H on graphene at different deposition stages and doping levels. Using plasma excitation frequencies larger than 100 MHz, instead of the standard 13.56 MHz, we provide a gentler deposition of a-Si:H onto graphene, as it is reported that ion energies decrease with increasing plasma excitation frequencies [2]. Here we will present the atomic force microscopy characterization of the different growth stages of a-Si:H on graphene, the electrical characterizations for the type of contact and IV behavior of these interfaces. [1] W. Mehr et al. Vertical graphene base transistor, IEEE Electron Device Lett, 33, 5 (2012). [2] G. Lupina et al. Plasma-enhanced chemical vapor deposition of amorphous Si on graphene, Appl. Phys. Lett. 108, 193105 (2016).

C.6.4
12:30 Lunch break    
 
2D materials and interfaces : -
14:00
Authors : Shivani Dhall, Mansavi Kumar, Mehar Bhatnagar, Bodh Raj Mehta
Affiliations : Indian Institute of Technology Delhi, Hauz Khas, New Delhi- 110016, India

Resume : In the present work, role of isolated palladium (Pd) and tin oxide (SnO2) nanoparticles (NPs) deposited on graphene (G) has been investigated in terms of gas sensing characteristics of ethanol and H2 gas at different temperatures. The difference in modification the properties of (SnO2)/G and Pd/G interfaces leads to improvement in selectivity and sensitivity of the chemiresistive sensors. It is observed that, incorporation of isolated Pd NPs on the graphene facilitates the room temperature sensing of H2 gas with fast response and recovery time. In contrast, isolated SnO2 NPs on graphene enables the detection of ethanol at room temperature. However, combination of isolated Pd and SnO2 NPs on graphene results in improvement in the sensitivity for both ethanol and H2 gas. The above results have been explained on the basis for interface formation between G and NPs. These results are important for developing a new class of chemiresistive type gas sensor based on change in the electronic properties of the G and NPs interfaces.

C.7.1
14:15
Authors : LE Thi Xuan Huong, Bechelany Mikhael, Cretin Marc
Affiliations : IEM (Institut Européen des Membranes), UMR 5635 (CNRS-ENSCM-UM2), Université de Montpellier, Place E. Bataillon, F- 34095, Montpellier, Franc

Resume : Over the past decade, Electrochemical Advanced Oxidation Processes (EAOPs) have experienced significant developments, showing great efficiency for the decontamination of wastewater polluted with toxic and persistent pesticides, organic synthetic dyes, pharmaceuticals and personal care products. The most popular technique among them is the electro-Fenton (EF) process, in which H2O2 is generated continuously at the cathode with O2 or air feeding while an iron catalyst (Fe2+, Fe3+, or iron oxides) is added to the effluent. Both iron and hydrogen peroxide react together to generate hydroxyl radicals, mainly oxidant for the treated solution, as shown in the following equations [1]: Fe2+ + H2O2 → Fe3+ + •OH + OH- Since this reaction takes place in acidic medium, it can alternatively be written as: Fe2+ + H2O2 + H+ → Fe3+ + •OH + H2O In this study, reduced Graphene Oxide (rGO) was electrochemically deposited on carbon felt (CF) in order to design a novel cathode applied in electro-Fenton (EF) process for the decontamination of wastewater polluted with persistent organic pollutants (POPs). The effective destruction of POPs by EF process is substantially dependent on the production of H2O2. This r-GO modified cathode enhanced the generation of H2O2 through the improvement of the hydrophilic characteristic and the conductivity of raw carbon felt, proved by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results [2]. The essential factors affecting the modification, such as current density value, time of graphene oxide (GO) deposition and electrochemical reduction to form reduced graphene oxide (rGO), were investigated. The structures of GO, rGO, CF and rGO-CF were characterized by SEM, XRD, XPS and contact angle measurements [3]. Degradation kinetics of dyes (Acid Orange 7) and pharmaceuticals (Paracetamol) were investigated and mineralization rate (i.e. conversion from organic to inorganic carbon) was determined. The degradation of POPs on rGO-CF cathode is much higher than on raw CF, proving that rGO-CF is a powerful promising electrode for improving removal efficiency of pollutants using EF technology. [1] Thi Xuan Huong Le, Christophe Charmette, Mikhael Bechelany, Marc Cretin, Facile Preparation of Porous Carbon Cathode to Eliminate Paracetamol in Aqueous Medium Using Electro-Fenton System, Electrochimica Acta 188 (2016) 378–384. [2] Thi Xuan Huong Le, Mikhael Bechelany, Joffrey Champavert and Marc Cretin, A Highly Active Based Graphene Cathode for Electro-Fenton Reaction, RSC Advances, 2015, 5, 42536 – 42539. [3] Thi Xuan Huong Le, Mikhael Bechelany, Stella Lacour, Nihal Oturan, Mehmet A. Oturan, Marc Cretin, High removal efficiency of dye pollutants by electron-Fenton process using a graphene based cathode, CARBON 94 (2015) 1003–1011.

C.7.2
14:30
Authors : M. González Cuxart [1], I. Šics [1], A. R. Goñi [2,3], E. Pach [4], G. Sauthier [4], H. Moreno Fernandez [1], V. Carlino [5], and E. Pellegrin [1].
Affiliations : [1] ALBA Synchrotron Light Facility, Carrer de la Llum 2-26, 08290 Cerdanyola del Vallès, Spain; [2] Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, Bellaterra, Spain; [3] ICREA, Passeig Lluis Companys 23, 08010 Barcelona, Spain. [4] Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain; [5] ibss Group Inc., Burlingame, CA 94010, USA.

Resume : Multiple layers of graphene thin films and graphene nano-sheets were grown on different substrates (i.e., polycrystalline nickel foil, Ni(111), HOPG(0001)) using remote Plasma-Enhanced Chemical Vapor Deposition (rPE-CVD). As a novel basic approach to this technique, a new remote low-pressure RF plasma source has been used to (i) minimize the effect of the plasma electrical field on the orientation of resulting graphene nano-sheets, (ii) decouple the dissociation process of the gas from the growth process of graphene on the substrate, (iii) warrant for a low graphene defect density via slow plasma kinetics, (iv) tune the feedstock gas chemistry in view of improving the graphene growth, and (v) reduce the growth temperature as compared to conventional chemical vapor deposition (CVD). In order to assess the quality of the resulting graphene layers Raman spectroscopy, x-ray photoemission spectroscopy, scanning electron microscopy, and scanning tunneling microscopy were used. A systematic characterization of the samples based on a sequence of measurements and detailed cross-checks - together with a comparison with other carbon allotrope references - is reported. Last but not least, the inherent "add-on" characteristics of this remote new plasma source warrants for a remote plasma deposition process compatible with typical UHV surface science requirements before/after the deposition process.

C.7.3
14:45
Authors : Minyeong Je, Youngbin Lee, Yong-Chae Chung
Affiliations : Department of Materials Science and Engineering, Hanyang University

Resume : In this study, the structural stability and electronic properties for two-dimensional (2-D) material were investigated using monolayer Cr2C, which is one of the MXene, with mixed functional groups. Interestingly, unlike the typically 2-D material with mixed functional groups, the F and OH functional groups on each side of Cr2C, Cr2CF(OH), have negligible effect on the magnetic and electronic characteristics of the other side. The unique phenomenon results from slight differences in the geometry of each functional group side, such as the coordination number, bond length, and thickness from those of Cr2CF2 and Cr2C(OH)2 despite the mixed functional groups. Because of the preserved magnetic moments of the Cr atoms bound with each functional group, Cr2CF(OH) shows ferrimagnetism without the entire offset of the magnetic moment. Similarly, the semiconducting properties with an indirect band gap are presented due to the relative position of the energy levels in each spin band whose atomic contributions are maintained from Cr2CF2 and Cr2C(OH)2, respectively. On the basis of these findings, when each surface of the monolayer Cr2C is terminated by the other functional groups, it is expected that the magnetic and electronic characteristics of Cr2C-based MXene are easily anticipated using the previous reported MXene with one functional group on each side.

C.7.4
15:00
Authors : Marie-Blandine Martin (1)(2), Sabina Caneva (1), Regina Galceran (2), Maëlis Piquemal-Banci (2), Robert Weatherup (1), Lorenzo D'Arsié (1), Indrat Aria (1), Raoul Blume (3), Robert Schloegl (3), Frédéric Petroff (2), Albert Fert (2), Bruno Dlubak (2), Pierre Seneor (2), Stephan Hofmann (1)
Affiliations : (1) University of Cambridge, Department of Engineering, CB30FA Cambridge, United Kingdom (2) Unité Mixte de Physique CNRS/Thales associated to Université Paris-Sud XI, 91767 Palaiseau, France (3) Helmholtz-Zentrum Berlin fur Materialien und Energie, 12489 Berlin, Germany

Resume : The recent discovery of 2D materials has opened up novel exciting opportunities in terms of functionalities and performances for spintronics devices. One of them is to address the issue of the oxidation of ferromagnetic materials which considerably limit the use of air/wet processes in the fabrication of devices. The recent progress on the growth of graphene and h-BN by chemical vapour deposition on top of ferromagnetic catalysts like Ni[1] or Fe[2] has permitted to circumvent this issue. We will first show how a thin graphene passivation layer can prevent the oxidation of a ferromagnetic electrode of Ni while adding a new interesting spin filtering property[3] . We will then present how this study enabled the use of the advantageous but oxidative technique of ALD to deposit homogeneous working sub-nanometer tunnel barriers in vertical spin valves[3]. We will finally highlight the passivation properties of a monolayer of h-BN on top of Fe and show the resulting successful integration of h-BN as a tunnel barrier in magnetic tunnel junctions[4]. These different experiments unveil promising uses of 2D materials for spintronics. [1] Weatherup et al ACS Nano 6, 9996 (2012) [2] Caneva et al Nanoletters 15, 1867 (2015) [3] Martin et al ACS Nano 8(8) 7890 (2014) [4] Piquemal et al APL 108(10), 102404 (2016)

C.7.5
15:15
Authors : Ghada H. Ahmed, Jiakai Liu, Manas R. Parida, Noktan Alyami, Riya Bose, Osman M. Bakr* and Omar F. Mohamed*
Affiliations : King Abdullah University of Science and Technology

Resume : Hybrid organic-inorganic perovskites have recently emerged as an important class of semiconductor materials, exhibiting remarkable performance in photovoltaics and light emitting applications. To further improve the device efficiency based on these materials, an insightful understanding of the interfacial charge transfer (CT) and charge recombination (CR) processes is highly required. Here, we report for the first direct experimental observation for the tremendous impact of perovskites nanocrystals (NCs) shape on the interfacial CT process in presence of a molecular acceptor. A dramatic change in CT and CR dynamics at the interfaces of three different NCs shapes: spherical, platelets and cubic are recorded in real time. Time-resolved data clearly demonstrated that the degree and the mechanism of interfacial CT and CR in these systems are greatly affected by the NCs shape. More importantly, the results demonstrated that the complexation on the surface of NCs acts as an additional deriving force for tuning the CT dynamics. Moreover, we found that CT at the interface of the spherical and cubic shape is static and dynamics in nature, respectively. On the other hand, platelets shape exhibits a combination of static and diffusion controlled mechanisms. This new observation opens up a new venue for further developing pervoskites NCs-based applications.

C.7.6
15:30 Coffee break    
 
2D materials and interfaces : -
16:00
Authors : Jana Zaumseil
Affiliations : Universität Heidelberg, Heidelberg, Germany

Resume : The selective dispersion of semiconducting carbon nanotubes (s-SWNT) by wrapping with conjugated polymers has enabled their application in electronic and optoelectronic devices such as field-effect transistors and light-emitting field-effect transistors. Here, we show that the dispersion process can be easily scaled-up while maintaining good photoluminescence yield (~2%) and nanotube length (>1 µm) to obtain s-SWNT networks with excellent optical and electrical properties. We demonstrate ambipolar charge transport and near-infrared light-emission in field-effect transistors based on monochiral and mixed networks of s-SWNT at low voltages. We investigate the influence of the nanotube diameter distribution on charge transport within the network depending on the applied gate voltage and thus charge carrier density. Voltage-dependent photoluminescence and electroluminescence spectra provide insight into the charge distribution among the different nanotubes. From these insights we can derive guidelines for optimized nanotube networks for high-performance field-effect transistors.

C.8.1
16:30
Authors : Larry Kwesi Sarpong, Prof. Michael Bredol
Affiliations : Muenster University of Applied Sciences (Fachhochschule Münster,Steinfurt Germany)

Resume : Alternating Current Powder Electroluminescence (ACPEL) is steadily reaching higher importance in research due to its advantages such as, low manufacturing cost, low operating voltages, flexible choice of substrates. Still, ACPEL devices face challenges in becoming more wide-spread due to the low amount of light produced. To address this problem, conductive materials like carbon nanotubes (CNTs) have been employed and shown promising results for the fabrication of ACPEL devices due to their high aspect ratio facilitating percolation, local field enhancement and high mechanical- and thermal conductivity. However, pristine CNTs exhibit constant agglomeration problems in solution due to the strong Van der Waals forces and pi-pi stacking interactions between individual tubes. Thus, CNT/phosphor mixtures are usually prepared by crude mixing of CNTs in organic solvents. In this work, we systematically investigated the interface chemistries of CNTs and ZnS phosphors in order to prepare pre-coupled semiconductor-carbon composites for ACPEL applications. Phosphor-carbon composites prepared in aqueous systems by heterocoagulation showed enhanced light output already at low CNT concentrations of 0.01 wt%. SEM images obtained did not only prove better distribution of the CNTs on the surface of the luminescent phosphor, but also proved that the heterocoagulation dynamics can be controlled by varying the mixing method, reaction time and pH.

C.8.2
16:50
Authors : Antonio Attanzio*, Andrei Sapelkin†, Felice Gesuele| Ming Zheng††, Matteo Palma*
Affiliations : * Materials Research Institute and School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK † Materials Research Institute and School of Physics and Astronomy, Queen Mary University of London, E1 4NS |CNISM and Dipartimento di Fisica, Università di Napoli “Federico II”, Via Cintia, 26, Naples 80126, Italy †† Materials Science and Engineering Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8542, United States

Resume : We present a controlled assembly strategy for the formation of carbon nanotube - quantum dot nanohybrids, where the terminal ends of individual single-walled carbon nanotubes (SWCNT) are selectively functionalised with single quantum dots (QDs), via the formation of covalent bonds. The assembly, in environmentally friendly and biocompatible aqueous solution, was controlled towards the formation of monofunctionalized SWCNT-QD structures. We use DNA wrapped carbon nanotubes, where the DNA acts as a surfactant for the dispersion of the nanotubes in water. Moreover, the DNA’s helical wrapping on the sidewalls of the tubes leaves only the terminal ends of the SWCNTs available for direct functionalization. Atomic force microscopy has been used to image the nanostructures and allowed us to identify the nanodots exclusively at the terminal ends of the tubes. Photoluminescence studies in solution and on surfaces at the single nanohybrid level showed evidence of electronic coupling between the two nanostructures. Quenching of photoluminescence of the CNT-QD nanohybrids in solution has been observed which indicates an electronic coupling between the two nanostructures as previously observed in QD-SWCNT composites. The photoluminescence blinking dynamics of conjugated and un-conjugated individual quantum dots was investigated showing larger off-state probability densities for QDs attached to the tubes, suggesting an increased photoinduced charging of the nanocrystals. The ability to covalently couple heterostructures with single particle control is crucial for the design of novel QD-based optoelectronic and light-energy conversion devices.

C.8.3
17:10
Authors : T. Ketolainen, V. Havu, M. J. Puska
Affiliations : COMP, Department of Applied Physics, Aalto University, P.O. Box 11100, FI-00076 Aalto, Finland

Resume : Experimental studies of semiconducting carbon nanotubes (CNTs) doped with gold chloride have shown a remarkable downshift in the Fermi level [1]. Furthermore, the sheet resistances of the CNT thin films have been found to decrease in the doping process [2]. In the present work, we investigate computationally the influence of AuCl4 molecules on the band structures and intratube electron transport of single-wall semiconducting CNTs as well as on the intertube transport. Calculations are carried out with the FHI- aims code package based on the density-functional theory within the hybrid functional and non-equilibrium Green?s function formalisms [3,4]. According to our results, there is a strong charge transfer from CNTs to AuCl4 molecules and CNTs become metallic. Moreover, AuCl4 molecules linking CNTs decrease remarkably the intertube resistance. The decrease of intertube resistance due to acid treatment has been seen also in experiments [2]. These two effects, metallization of CNTs and decrease of the contact resistance, improve significantly the conductivity of CNT networks. [1] K. K. Kim et al., J. Am. Chem. Soc. 130, 12757 (2008). [2] A. Znidarsic et al., J. Phys. Chem. C 117, 13324 (2013). [3] V. Blum et al., Comput. Phys. Commun. 180, 2175 (2009). [4] T. Ketolainen et al., J. Chem. Phys. 142, 054705 (2015).

C.8.4
 
Poster Session 2 : -
17:30
Authors : S.?. Sydorenko1), S.?. Voloshko1), ?.P. Burmak1), ?.A. Vasylyev2), B.N. Mordyuk2)
Affiliations : 1) National Technical University of Ukraine ?KPI?, 37 Peremogy Ave., UA-03056 Kyiv, Ukraine; 2) G. V. Kurdyumov Institute for Metal Physics, N.A.S. of Ukraine, 36 Academician Vernadsky Blvd., UA-03680 Kyiv, Ukraine;

Resume : The processes of anomalous mass transfer are studied in the Al?Fe system. An aluminum alloy 2024 (D16) were processed with ultrasonic impact treatment (UIT) using a pin or intermediate plate made from Armco-iron. The UIT process was carried out at the amplitude of ultrasonic horn tip of ~25 ?m for different time (50 s to 250 s) under quasi-hydrostatic shock compression of the diffusion pair in air or neutral environment (argon) to avoid the oxidation of the contacting surfaces. When an intermediate Armco-Fe plate was used, the maximum concentration of Fe in the surface layer of the UIT-processed 2024 alloy was of ~10 at.%, and segregations of Cu (up to 30 at.%) were also observed in some local surface areas. After UIT, the surface of Armco-Fe plate contacted with the 2024 alloy contained up to 90 at.% of Al, and mass transfer other components of the 2024 alloy (Cu, Mg and Sn) occurred. The use of the Armco-Fe pin at UIT results in the intensification of the Fe mass transfer deep into the surface layer of the 2024 alloy, and in the formation of banded structure with different phase and elemental compositions of each of the bands, which depend on the duration and environment of the UIT process. In this case, the surface of the Armco-Fe pin did not contain Al or other components of the 2024 alloy. Double increase in microhardness of the 2024 alloy after UIT in a neutral environment (HV ~3 GPa) in comparison with that of the initial state (HV ~1.4 GPa) was observed regardless the presence or absence of the Armco-Fe plate between the treated surface and loading instrument. Severe plastic deformation of the surface layers of the 2024 alloy at the UIT through the Armco-Fe plate occurs less intensively because of the lower impact energy, which is partially dissipated by the Armco-Fe plate. Thus, to explain aforementioned similar magnitudes of microhardness we should account for some additional factor providing surface hardening of the 2024 alloy at presence of Armco-Fe. It is suggested that this factor is mechano-chemical interaction of Al with Fe and Cu, which promotes the formation of inclusions of Al-Cu-Fe intermetallic phases. The highest hardening (up to ~8 times) observed after the UIT process of 2024 alloy the Armco-iron pin in air environment was explained both by the essentially decreased size of coherent scattering areas and by the increased microstrains in crystalline lattice, as well as by the mechano-chemical oxidation of the processed surface during the severe plastic deformation at UIT.

C.8.5
17:30
Authors : Rangarajan Bakthavatsalam, Subrata Ghosh, Ratul Kumar Biswas, Aayushi Saxena, Alagar Raja, Musthafa Ottakam Thotiyl, Sandip Wadhai, Arun G. Banpurkar and Janardan Kundu*
Affiliations : CSIR-NCL Pune; CSIR-NCL Pune;CSIR-NCL Pune;CSIR-NCL Pune;IISER Pune; IISER Pune; Savitribai Phule Pune University; Savitribai Phule Pune University; CSIR-NCL Pune

Resume : Galvanic replacement reaction (GRR) involves a redox couple wherein oxidation of a metal and deposition of another metal occurs simultaneously. GRR, when occurs on a nanoscale template material, can yield nano structures with tunable morphologies and composition in a very facile, simple, and rapid manner. Here, we showcase how GRR can be effectively utilized to fabricate i) Cu dendritic structures with superior catalytic activity and exhibiting superhydrophobicity; 2 ii) Cu2O-Ag semiconductor-metal heterostructures, useful for SERS based chemical sensing and photocatalysis, showing evidences of facet selectivity in GRR. The report on the Cu dendritic structures is the first comprehensive and in-depth study on fabrication, characterization of Cu dendrites with superior performance in its application till date. The Cu2O-Ag heterostructures synthesized here, is one of the very few reports on utilizing Cu2O as template for Ag nanoparticle deposition on variety of templates (octahedra, cubes, cuboctahedra) that shows evidences of facet selectivity during GRR. Deposition of Ag on Cu2O through templated GRR has not been studied as extensively as has been for Au. Moreover, we show that an added surfactant (5-Sulfosalicylic acid, SSA) is necessary for the nucleation of Ag NPs on Cu2O template. Such nanostructures are highly beneficial for many applications such as SERS, self-cleaning surfaces and catalysis as demonstrated here.

C.8.6
17:30
Authors : Mohamed A. Abaza, Khaled M. Youssef
Affiliations : Materials Science & Technology Department, Qatar University

Resume : Nanocrystalline (nc) materials, defined as those with a grain size less than 100 nm, have proven to attain exceptional mechanical properties such as strength and hardness that exceed those of coarse-grained and counterparts. However, these nanostructures are inherently unstable at elevated temperature, which limits their service temperatures and expected lifetime. That is mainly because the nano-scale grain size provides a very large driving force for grain growth. Here we thermodynamically stabilized the nanostructure of pure Cu via segregation of Nb at the grain boundaries. This segregation tends to reduce the grain boundary (GB) energy and prevent grain growth at elevated temperatures. The Cu-1%Nb nanostructure was analyzed using X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) techniques. Mechanical properties as a function of annealing temperature were evaluated using Vickers microhardness test. Nano precipitation of Nb occurs at high temperature, which also could pin the grain boundary mobility and allow attaining a hardness value of 2.85 GPa (about 10 times higher than that of conventional coarse grained Cu) after annealing at 1073K, which is about 80% of the Cu homologous temperature.

C.8.7
17:30
Authors : S.M. Voloshko*, A.P. Burmak*, M.A.Vasylyev**, B.N. Mordyuk**
Affiliations : *National Technical University of Ukraine ‘KPI’, 37 Peremogy Ave., UA-03056 Kyiv, Ukraine; **G. V. Kurdyumov Institute for Metal Physics, N.A.S. of Ukraine, 36 Academician Vernadsky Blvd., UA-03680 Kyiv, Ukraine;

Resume : D16 aluminum alloy was treated by ultrasonic impact treatment (UIT) in chemically active and neutral atmospheres under quasi-hydrostatic compression, that provided surface strengthening more efficient comparing to the heat treatment and classical UIT schemes. It was shown that simultaneously to the low-temperature deformation of grainstructure dispersion it is possible to form durable oxide coatings with the thickness of several tens of micrometers on the alloy surface by means of UIT on the air. Increasing D16 surface microhardness (up to 2.5 times) by ultrasonic impact treatment in the inert atmosphere (Ar, He) was caused by the modification of dislocation structure, nanocrystalline structure formation due to the deformation and formation of nanoscale precipitates of S'- Al2CuMg hardening phase. It was shown the unique opportunity of increasing surface microhardness (up to ~ 5 times) by ultrasonic impact treatment in liquid nitrogen (77.4 K), due to the influence of synergistic processes of nanostructure formation and mechanochemical interaction of Al with N during cryodeformation. The model of surface strengthening by means of structure and phase mechanisms was offered.

C.8.8
17:30
Authors : S.M. Voloshko*, A.P. Burmak*, S.S. Kukharyk*, M.A.Vasylyev**
Affiliations : *National Technical University of Ukraine ‘KPI’, 37 Peremogy Ave., UA-03056 Kyiv, Ukraine **G. V. Kurdyumov Institute for Metal Physics, N.A.S. of Ukraine, 36 Academician Vernadsky Blvd., UA-03680 Kyiv, Ukraine

Resume : To improve the fatigue strength of a wide range of the metallic materials methods of the surface severe plastic deformation are used [1, 2]. Investigated the influence of ultrasonic shock treatment (USST) in an inert atmosphere on the structure, phase composition and micromechanical properties of composite coatings formed by embedding of dispersed particles of Al2O3, B4C, BN hardening powders and carbon nanotubes into the surface layers of D16 aluminum alloy. Under influence of severe plastic deformation caused by USST, a partial grinding and powder particles implementation and the nanostructuring of matrix alloy with the deformation composite layers take place. The observed maximum strengthening (200 - 350%) and durability increase (~ 7 times) of D16 alloy surface undergoing due to reinforcement by Al2O3 and B4C particles.

C.8.9
17:30
Authors : S.I. Sidorenko*, M.A.Vasylyev**, S.M. Voloshko*
Affiliations : *National Technical University of Ukraine ‘KPI’, 37 Peremogy Ave., UA-03056 Kyiv, Ukraine; **G.V. Kurdyumov Institute for Metal Physics, N.A.S. of Ukraine, 36 Academician Vernadsky Blvd., UA-03680 Kyiv, Ukraine;

Resume : First sandblasted (SB) of the titanium alloy Ti6Al4V surface at the temperature of liquid nitrogen (-196○C) was performed. For comparison, a standard trestment used as SB in the air under the same parameters and duration. It was shown that the major differences relate microhardness changes roughness, character morphology residual amount of the abrasive particles of Al2O3 on the surface. It was studied in detail the chemical composition in the different local areas of the alloy surface after the SB at room and cryogenic temperatures, as well as their degree of oxidation. It is planned to obtain experimental evidence regarding the fact that the low-temperature sandblasting improves wear resistance of the dental implants in chewing loads improves the corrosion resistance and adhesion strength biocompatible coatings applied to titanium substrate after SB in liquid nitrogen, and thus contributes significantly longer service life.

C.8.10
17:30
Authors : S.І. Sydorenko, S.М. Voloshko, А.І. Oleshkevych, А.K. Orlov
Affiliations : National Technical University of Ukraine "KPI"

Resume : Process developing at a free surface of thin metal layers, layered compositions of metals and metal alloys of nanometer thickness thermodynamically determine laws of diffusion mass transfer in the volume. These laws have features of superposition of formation processes of structural and concentration and concentration-phase inhomogeneities due to time distribution of different dominant diffusion mass transport mechanisms (boundary diffusion, diffusion by volume, surface diffusion) with "distortion" of the balance of the driving forces, the idea of which historically formed due to nanoscale factor. As a result during diffusion redistribution in such systems concentration gradients persist and homogeneous concentration distribution is not achieved, unlike processes in a bulk state. Experimental confirmation of this hypothesis has been discovered for a number of multi-layer systems obtained by condensation in a vacuum: Cu-Me (Me – Ni, Mn, Sn, Cr, Co), Cu-Mn-Sn, Cu-Cr-Al, Cu-Ni-Au, Cr-Cu-Ni, Cr-Cu-Ni-Au, Al – Me (Me – Ti, Ni, V, Cr, Ta, Mo, Co), Me-Si (Me – Mo, Ti, Cr, W, Ni, Pt), Pt-Ni-Si, Ni-Ti-Si, Ti-W-Si, Au-Co-Si, Al-Ti-W-Si, Au-Ni-Me-Si (Me – Mo, W, Ti), Au-Me-Mo-Si (Me – Co, Ni, Pt, Pd) etc. We consider the regularities of physical and chemical processes of phase formation on the free surface of nanoscale film compositions that develop during thermal treatment in oxygen- and hydrogen atmospheres. phenomenological and analytical models to describe these processes have been suggested. We discuss the impact of nanoscale factor, which manifests itself in the fact that the phase formation occurs in other sequences and other temperature ranges than it is in the case of bulk materials; phase atypical for solid state are formed in certain temperature ranges. Material science criteria to increase thermal stability of film compositions are predicted based on the analysis of thermodynamic parameters of phases formed and additional driving forces of mass transfer due to the influence of external surface and nanoscale factors.

C.8.11
17:30
Authors : Jungwook Woo; Kyung-Han Yun; Yong-Chae Chung
Affiliations : Department of Materials Science and Engineering, Hanyang University

Resume : Graphene monoxide (GMO), a newly two-dimensional material, is the promising candidate for nanoelectronic device due to its proper band gap for transistor and the high carrier mobility induced by the its low effective mass [1-2]. In this study, we investigated the geometric and electronic structure of bilayer GMO and the influence of the external electric field on bilayer GMO through density functional theory (DFT) calculation. All cases of bilayer GMOs show weak van der Waals interaction similar to typical interlayer bonding of two dimensional bilayer systems. The bilayer GMOs are predicted to have proper band gap for electronic device application (0.418 ̶ 0.448 eV). Above all, when applying the electric field to bilayer GMO, the band gap of bilayer GMOs responds more sensitively to the external electric field than the other bilayer two-dimensional system and thereby the semiconductor-metal transition (SMT) occurs in range of 0.21 ̶ 0.3 V/Å. [1] E. C. Mattson et al., Evidence of nanocrystalline semiconducting Graphene monoxide during thermal reduction of graphene oxide in vacuum, ACS nano, 12, 9710-9717 (2011) [2] H. H. Pu et al., Strain-induced band-gap engineering of graphene monoxide and its effect on graphene, Physical review B, 87, 085417 (2013)

C.8.12
17:30
Authors : Gaehang Lee, Ki Min Nam
Affiliations : Korea Basic Science Institute(KBSI), Daejeon 305-806, Korea (Gaehang Lee); Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Korea (Ki Min Nam)

Resume : We present the sustainable synthetic process of Fe3O4 nanocrystals. Thermal decomposition of Fe(acac)3 in 1-hexadecanol leads to the formation of Fe3O4 nanocrystals with controlled size and morphology. Formation mechanisms have been elucidated on the basis of GC-MS analysis, which make it possible to large-scale preparation. Structural characterization has been carried out by TEM and XRD. Moreover, we have prepared Fe3O4 nanocrystals with the recycled solvent recovering from initial process. The resulting Fe3O4 shows increased average sizes with irregular pores in nanocrystals. Because 1-hexadecanol can be used repeatedly without any waste, the whole process consumes only iron precursor. This synthetic method has high yield, good reproducibility, and convenient process, which make it possible to large-scale preparation for industrial application.

C.8.13
17:30
Authors : Bibi Ruqia, Heejin Kim, Sang-Il Choi*
Affiliations : Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Korea

Resume : Platinum shows outstanding catalytic activity for electrochemical reactions in polymer electrolyte membrane fuel cells. However, the limited reserves and high cost of Pt have directed recent researches toward finding ways to reduce Pt loading by enhancing its catalytic activity and stability. Controlling the shape of Pt nanocrystals is one of the important strategies that influences binding strength between Pt active sites and the adsorbed chemical species thus the catalytic activity. Currently, Pt octahedra enclosed by {111} facets show higher catalytic activity toward oxygen reduction reaction compared to the Pt cubes enclosed by {100} facets. However, those studies revealed the synthesis of Pt octahedra by incorporating transition-metal additives as a capping agent, which could be alloyed with Pt during the synthesis. Because the catalytic activity of Pt-based catalysts is highly dependent on the alloying metals, it is needed to prepare pure Pt octahedra and cubes to investigate the catalytic behavior on Pt{111} and Pt{100} facets. We here introduce, as the first time, a facile synthesis of Pt octahedra and cubes by manipulating the reduction kinetics without adding any metal additives. The morphologies of well-controlled Pt octahedra and cubes were observed by typical transmission electron microscopy.

C.8.14
17:30
Authors : Mariusz Barczak, Katarzyna Pi?tkowska-Sawczuk, Piotr Borowski
Affiliations : Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland

Resume : Nowadays, there is an emergent expectation and demand for developing efficient protocols for controlling the emissions of pharmaceuticals to reduce their presence in waters and wastewaters. Processes based on adsorption are particularly promising because of their high efficiency, low cost, versatility, as well as availability of different adsorbents. It should be emphasized that successful applications of adsorption processes cannot be considered separately from the production of new adsorbents on both the laboratory and industrial scales. One of the widely studied class of potential sorbents are nanoporous silica materials. Those materials possess high specific surface areas, well-ordered pore structures with adjustable uniform mesopores, and large pore volumes. In addition, their surfaces can be easily functionalized to create tailored surface chemistry. As a result of surface and structural properties, their applications as adsorbents in various environmental processes related to the removal of pollutants from water including heavy metals, dyes and pharmaceuticals have been extensively studied. Above-mentioned exceptional properties of nanoporous silica materials are very attractive particularly for the adsorption of biological molecules, particularly bulky ones such as pharmaceuticals. The aim of this lecture is to provide a brief up to date review of nanoporous silica materials as potential sorbents of pharmaceuticals from waters and wastewaters, as well as to present our own experimental results on the silica-based nanoporous materials? design and synthesis. Strategies on the synthesis and the resulting properties with respect to the envisaged applications will be discussed.

C.8.15
17:30
Authors : Weiping Gong1, Yajie Li1, Jinxiang Song1, M. Fedorov2, S. Zamulko2, S. Konorev2, S. Voloshko2, S. Sydorenko2
Affiliations : 1. Laboratory of Electronic Functional Materials, Huizhou University 2. Metal Physics Department, National Technical University of Ukraine “Kyiv Polytechnic Institute”

Resume : General approaches were formed by us to the organization of computer calculations based on the «data base science and computer materials design» methodology applied to increasing of temperature and time stability and reliability of thin-film metal contacts for new generation of solar cells. To solve the "computer materials design" problems we have proposed and tested the interpolation approach, which involves the solving both direct and inverse problems. The aim of solving of the direct problem is the construction of the interpolation polynomial from the existing discrete databases, where all compositions or part of the composition intervals are in correspondence with the physical properties. After the construction of such interpolation polynomial the inverse problem is solved: what materials compositions can provide the predetermined properties. Solving of the inverse problem requires a large number of costly experiments (inverse problem of the 1st kind), some of which can be changed through the application of quantum simulation modeling methods (inverse problem of the 2nd kind), e.g. – ab initio methods. According to the developed interpolation approach we made the necessary calculations and defined the prospective search areas of metallic materials compositions and combinations that will slow down the processes of solar cells degradation.

C.8.16
17:30
Authors : Sumera Shimizu, Shinichi Ito, Hideo Asai, Toshihiko Miyakawa, Masataka Muto, and Syunji Kajikawa
Affiliations : DENSO Corp. Materials Eng. R & D Div., 1-1, Showa-cho, Kariya, Aichi

Resume : A passive film is very important to a corrosion resistance of stainless steel. SUS304 steel has the higher resistance than many other stainless steels. This is due to that its passive film is naturally formed and self-regenerated at ordinary temperature and pressure1): SUS304 is a native functional material. As structures of the film on SUS304, two models have been ever proposed2),3). One of them is a network structure composed of Cr-oxide and -hydroxide, and the other is a bilayer structure of Cr-hydroxide/-oxide/SUS304. However, the definitive experimental evidences have not been reported yet. In this study, we investigated the detailed structure using synchrotron XAFS and XPS. To achieve surface sensitive XAFS spectra, the conversion electron yield (CEY) mode was adopted. The Cr-K edge CEY-XAFS spectrum clearly showed an atomically ordered network structure (at least <10 Å) similar to an Cr(IV) oxide. The FEFF simulation revealed that the crystal lattice of the network is “rutile type”. The high resolution O 1s XPS spectrum showed that the local structure of the network is a chromium oxyhydroxide (e.g., -O-Cr-OH-), which forms by a reaction between the oxide and water. Also, besides the network, the normal Cr(III) oxide was independently observed in the film. Since the O 1s peak ratio of the normal oxide to the network increased with incident photon energy, it was indicated that the oxide deposits near the interface of the film/SUS304. These results explain that the base metal is prevented from corroding by the dense passive film. We hope to apply the network structure to other steels in order to make more functional SUS. 1) Massoud et al. J. Electrochem. Soc., 2013. 2) Okamoto, Corros. Sci., 1973. 3) Maurice, J. Electrochem. Soc., 1996.

C.8.17
17:30
Authors : Michal D. Wlodarski [1], Jinbo Pang [2], Pawel S. Wrobel [1], Slawomira Pusz [1], Zhongfan Liu [3], Barbara Trzebicka [1], Mark H. Rümmeli [1, 2, 4], Alicja Bachmatiuk [1, 2]
Affiliations : [1] - Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, Zabrze 41-819, Poland; [2] - IFW Dresden, Institute for Complex Materials, P.O. Box D-01171 Dresden, Germany; [3] - Center for Nanochemistry (CNC), Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China; [4] - College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, P. R. China

Resume : We show that the type of copper foil pre-treatment has a significant influence on the resultant graphene formed. We explored electropolishing with two different solutions: 1) water solution of phosphoric acid and 2) a mixture of phosphoric acid, water, ethanol, isopropanol and urea. Samples were electropolished for different voltage and time. The quality of the surface after electropolishing was measured by AFM, SEM and UV-Vis to compare their roughness and reflectance. Before graphene growth the copper foils were annealed in air in order to remove unwanted carbon residuals and in a hydrogen atmosphere to reduce the surface and also to rebuild the crystalline structure. The quality of the grown graphene was measured using light microscopy, SEM and Raman spectroscopy. We show that the surface quality has significant effect on the way that graphene grows.

C.8.18
17:30
Authors : Vladimir Maryasin (1), Quentin Rafhay (1), Davide Bucci (1), Jérome Michallon (2), Federico Panicco (1), Claire Verrier (1), Alain Fave (3), Anne Kaminski-Cachopo (1)
Affiliations : (1) Université Grenoble Alpes, IMEP-LAHC, Minatec, Grenoble INP, F-38000 Grenoble, France (2) IPVF, Antony, France (3) Université de Lyon, INL, INSA-Lyon, F-69100 Villeurbanne, France

Resume : Nanowire-based solar cells are attractive due to their ability to increase light absorption while reducing the amount of material used in thin film photovoltaic devices. In particular, III-V nanowires can be grown on silicon substrates to form a tandem solar cell, a promising system able to reach high efficiencies at relatively low costs. However, the design of such solar cells should be carefully optimized to obtain high absorption of light and efficient collection of carriers. In this work the optical and electrical simulations are coupled in order to define the optimal structure for tandem solar cells based on GaAlAs nanowire on silicon. Electromagnetic simulations are carried out with the home-made RCWA software to define the best NWs geometry for the absorption of light under current matching conditions. The optimal geometries deduced from the optical simulation are then used for the electrical simulation. The coupling between optical and electrical simulations is performed by computing a map of the optical generation rate in the structure, which is used as an input for the electrical simulation via the commercial TCAD software Sentaurus. From the electrical simulation, the power conversion efficiency is deduced which allows to analyze the influence of carrier transport mechanism, bulk and interface recombination, junction depth and doping profile, tunnel junctions, etc. in the multijunction structure.

C.8.19
17:30
Authors : Dhruv Singhal* 1,2,4, Olivier Marconot 1,2 , Marc Zelsmann 3, Pascal Gentile 2, Dimitri Tainoff 4 , Olivier Bourgeois 4 and Denis Buttard 2,5
Affiliations : 1 Université Grenoble Alps, Grenoble, France; 2 INAC/PHELIQS/SiNaPS, CEA Grenoble, 17 Avenue des Martyrs, 38000 Grenoble, France; 3 LTM-CNRS, CEA-LETI-MINATEC, 17 rue des Martyrs, 38000 Grenoble, France; 4 Institut Neel, CNRS, 25 Avenue des Martyrs, 38042 Grenoble, France; 5 Université Joseph Fourier/IUT-1, 17 quai C. Bernard, 38000 Grenoble, France;

Resume : Thermoelectric modules interconvert thermal gradients for power generation through Seebeck effect. Restricted by its low efficiency, measured by a dimensionless parameter ZT (function of Seebeck coefficient, electrical and thermal conductivities), it finds niche applications. Nanomaterials allow tailoring of the interdependent parameters, which opens up new avenues to enhance efficiency. Low thermal conductivity with a wide range of density of states and phonon electron scattering in nanomaterials make them ideal for thermoelectric applications. When the dimensions of the material are comparable to the mean free path of the phonons, the thermal conductivity drops significantly due to surface scattering mechanism. Nanowires with modulated diameter would further decrease the thermal conductivity substantially as the corrugations would act as a trap for phonons and reduce transmitivity. In this work, dense forest of diameter-modulated silicon nanowires will be grown through template-assisted Chemical Vapor deposition (CVD). Nanoporous alumina, commonly used as templates, is fabricated by anodizing aluminum in acidic electrolytes. The diameter and porosity of the template depend largely on the applied voltage. In order to fabricate porous template with modulating pore diameter, method of pulse anodisation is employed which consists of periodic potential surges. Structural engineering along the film growth direction is achieved by deliberately designing the potential pulse sequences. The arrangement of the pores on the surface is improved by the use of nanoimprint lithography and double anodisation method. The resulting highly ordered and dense structure of modulated pore diameter is suitable as templates for growing nanowires. The diameter of the Si nanowire segment is predefined by the internal pore structure of alumina. Growth of Si nanowires is underway through CVD. Sensitive 3-omega measurements will be carried out on the forest of nanowires to confirm the reduction in the thermal conductivity of Silicon.

C.8.20
17:30
Authors : Pawel S. Wrobel [1], Michal D. Wlodarski [1], Slawomira Pusz [1], Andrzej Marcinkowski [1], Zhongfan Liu [2], Barbara Trzebicka [1], Mark H. Rümmeli[1, 3, 4], Alicja Bachmatiuk [1, 4]
Affiliations : [1]- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, Zabrze 41-819, Poland; [2]- Center for Nanochemistry (CNC), Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China; [3]- College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, P. R. China; [4]- IFW Dresden, Institute for Complex Materials, P.O. Box D-01171 Dresden, Germany.

Resume : We demonstrate the chemical modification of graphene oxide and the influence of its chemical composition on its sensing ability. Graphene oxide was obtained using a modified Hummers’ method. Additionally, we explored the samples reduced with ascorbic acid and sodium borohydride and also investigated the impact of thiol functional groups on its sensing ability. The sensors were fabricated via drop coating of graphene-based material onto interdigitated chip surfaces. Basic analysis of the explored materials were performed with FTIR spectroscopy, Raman spectroscopy, scanning electron microscopy (lateral size) and atomic force microscopy (height). The sensing responses were measured for different concentrations of ethanol vapors and nitrogen dioxide.

C.8.21
17:30
Authors : Dmitrii V. Shuleiko (1), Fedor V. Kashaev (1), Stanislav V. Zabotnov (1), Denis E. Presnov (2,1), Andrey G. Kazanskii (1), Leonid A. Golovan (1), Pavel K. Kashkarov (1)
Affiliations : (1) Lomonosov Moscow State University, Faculty of Physics, 1/2 Leninskie Gory, Moscow, 119991, Russia; (2) Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, 1/2 Leninskie Gory, Moscow, 119991, Russia

Resume : Femtosecond laser pulses with high emission intensity and low photon energy can be used for uniform modification of a-Si:H films [1] and to achieve anisotropy of their structural, electrical and optical properties. For example, surface periodic structures (ripples) can be produced [2]. In this paper, a-Si:H films treated by femtosecond laser pulses (1250 nm, 100 fs) were investigated. A surface profile with period equal to the laser spot diameter (150 μm) was formed by means of laser beam movement in the raster mode. Scanning electron microscopy also revealed presence of the ripples, perpendicular to polarization of the incident beam on the treated surface, with 0.36±0.03 μm period. The electric conductivity of a-Si:H film after irradiation with femtosecond laser pulses increases by almost 3 orders of magnitude due to dehydrogenation and nanocrystallization of the film [3]. Due to non-uniform crystallization of amorphous silicon and the electric field depolarization by periodic structure, the conductivity along the scan lines and periodic structures is almost threefold greater than in the perpendicular. The work was financially supported by the Russian Foundation for Basic Research (project 16-32-80066). [1] A. V. Emelyanov, M. V. Khenkin, A. G. Kazanskii, et al. Thin Solid Films 556, 410 (2014) [2] R. Drevinskas, M. Beresna, M. Gecevičius et al. Appl. Phys. Letters 106, 171106 (2015) [3] A.V. Emelyanov, A.G. Kazanskii, P.K. Kashkarov et al. Semiconductors 46, 769 (2012)

C.8.22
17:30
Authors : Elizabeth Polido Legaria, Vadim G. Kessler, Gulaim A. Seisenbaeva
Affiliations : Department of Chemistry and Biotechnology, Biocenter, SLU, Box 7015, 75007 Uppsala, Sweden,

Resume : Rare Earth Elements (REE) are a group of 17 metals (the so-known as lanthanides plus Ytrium and Scandium), which are increasingly important for many emerging modern applications. Therefore, the development of technologies for their recycling has become a significantly relevant research topic. In this work, a magnetic hybrid nanoadsorbent consisting of an iminodiacetic acid (H2IDA) organosilane derivate grafted onto SiO2 covered g-Fe2O3 nanoparticles was synthesized and fully characterized by FTIR, TGA and 13C CP-MAS solid state NMR. The silica coating process was optimized, resulting in highly stable core-shell nanoparticles. Both REE uptake capacity and desorption efficiency in acidic media were tested by complexometric titration and SEM-EDS analysis revealing very effective and competitive uptake. Selectivity studies with binary REE mixtures revealed a slightly higher capacity towards heavier REE and an appreciable selectivity, especially on desorption. The complexation of the molecular H2IDA with REE under neutral conditions was investigated by single cristal X-Ray Crystallography to produce relevant molecular models, showing an unexpected difference in coordination numbers and binding mode of IDA that potentially provides an explanation for the observed selectivity.

C.8.23
17:30
Authors : A. Nicolenco, N. Tsyntsaru, V. Hoffmann, H. Cesiulis
Affiliations : Vilnius University, Dept. Phys. Chem., Naugarduko 24, Vilnius LT-03225, Lithuania; Institute of Applied Physics of ASM, 5 Academy str., Chisinau, MD – 2028, Moldova; Leibniz Institute for Solid State and Materials Research Dresden, Helmholtzstraße 20 , 01069 Dresden, Germany; Vilnius University, Dept. Phys. Chem., Naugarduko 24, Vilnius LT-03225, Lithuania;

Resume : The functional properties of alloys electrodeposits are defined by the chemical composition including incorporated non-metallic elements such as H, C or O. The quantitative determination of full composition of electrodeposits often is a methodic challenge. In this study the incorporated oxygen and its distribution along the entire thickness of deposited Fe-W layer was investigated by means of glow discharge optical emission spectroscopy (GD-OES) using instrument (Spectruma GDA750). It was calibrated for light elements such as O, H, S and Na using in-house prepared sintered samples. Fe-W alloys were electrodeposited at 20°C and 65°C from glycolic-citrate bath of following composition: 1 M glycolic acid, 0.3 M citric acid, 0.1 M (Fe)2(SO4)3 and 0÷0.5 M Na2WO4; pH 6.5. The influence of bath composition and deposition conditions on distribution of elements in alloyed materials was investigated by GD-OES. Increase in tungstate concentration in the bath from 0.05M to 0.4 M results in the increase in tungsten content from 2 at% to 28 at%. EDS analysis shows a considerable amount of oxygen on the surface and apparent value in some cases exceeds 50 at % (EDS data) while in the deeper layers amount of oxygen is ~15 at.% (GD-OES data). Acknowledgments: Authors acknowledge funding from H2020 (project SELECTA 642642), Research Council of Lithuania (MIP-031/2014) and Moldavian national project (15.817.02.05A). We are also grateful for the cooperation with Spectruma Analytical GmbH.

C.8.24
17:30
Authors : Jérôme Michallon1, Julie Goffard2, Pierre Rale2, Laurent Lombez3, Fabien Molica3, Negar Naghavi3, Stéphane Collin2
Affiliations : 1 Institut Photovoltaïque d'Ile-de-France (IPVF), 8 rue de la Renaissance, 92160 Antony, France 2 Laboratoire de Photonique et de Nanostructures (LPN/CNRS), Route de Nozay, 91460 Marcoussis, France 3 IRDEP, UMR EDF-CNRS-Chimie Paristech, EDF R&D, 6 quai Watier BP 49, 78401 Chatou CEDEX, France

Resume : CIGS is one of the most promising materials for the fabrication of cost-efficient solar cells, with record power conversion efficiencies above 22 %. In the context of a constant cost reduction, material savings are required for the long-term competitiveness of CIGS solar cells. It can be achieved in ultrathin solar cells with efficient light trapping structures such as nanostructured back mirrors. However, surface recombination at front and rear contacts play an increasing role as the thickness of the CIGS absorber is reduced. In this context, the concept of passivated emitter rear contact (PERC) Si solar cells based on small contacts (i.e. point contacts) surrounded by a passivation layer has been adapted to CIGS solar cells. In this work, we present an in-depth analysis and comparison of passivation layers (Al2O3, SiO2, TiO2) deposited on CIGS. The effect of the passivation layers on the recombination are investigated by steady and time-resolved photoluminescence and cathodoluminescence characterizations, as well as by LBIC and EBIC measurements. Device simulations, calibrated with measured samples, are also used to optimize the spacing between point contacts and get insight in the recombination processes in CIGS solar cells.

C.8.25
17:30
Authors : Sandip Paul Choudhury, Ayon Bhattacharjee
Affiliations : National Institute of Technology Meghalaya, Shillong, India

Resume : Tin oxide is a widely used transparent conducting oxides and has numerous application. A theoretical study of the same is equally important. Density Functional Theory (DFT) study was performed to analyse the effect of Ni doping on SnO2. GGA-PBE exchange correlation function is used along with basic set of double numeric quality (DNP) to carry out the calculations. The energy convergence tolerance limit was 1.0 x 10-5 Ha/atom. The electronic properties were studied and band structure and density of states of the doped and undoped sample was explored. Electronic structure of Ni doped sample in comparison to pure sample showed better conductivity results. The effect of doping was analysed from density of states graph. A 48-atom SnO2 super cell is considered and Ni atom was used as a dopant for three different structures. Cases were considered for both interstitial and substitutional locations of Ni atom.

C.8.26
17:30
Authors : Song Mi Lee¹, Sung-Ho Shin², Junghyo Nah², Min Hyung Lee¹*
Affiliations : ¹ Department of Applied Chemistry, Kyung Hee University, Yongin, Gyeonggi 17104, Korea; ² Department of Electrical Engineering, Chungnam National University, Daejeon 34134, Korea

Resume : The key factor for efficient water splitting is to optimize band bending at the interface between the semiconductor and electrolyte. Our approach is to induce dipoles inside photoelectrochemical cells (PECs) to lead band bending favorable for water splitting. Ferroelectric materials that have a spontaneous polarization can be one promising material as their polarization domains can be aligned in the desired direction by a poling process. In this work, the vanadium (V)-doped ZnO nanosheets (NSs) were synthesized to apply ferroelectric property as photoanodes for water splitting and systematically investigated poling effects. Spontaneous polarization was induced suitable band bending between photoanodes and electrolyte. As a result, positively polarized PEC electrodes improved water splitting efficiency compared with negatively polarized ones.

C.8.27
17:30
Authors : Young Eun Bae¹ and Min Hyung Lee*¹
Affiliations : ¹ Department of Applied Chemistry, Kyung Hee University, Yongin, Gyeonggi 17104, Korea.

Resume : The molybdenum sulfide conjugated materials are the most eminent alternative to Pt for hydrogen evolution reaction catalyst. Heterojunction structures of MoO₃/MoS₂ were fabricated by chemical vapor deposition (CVD) of MoO₃ followed by shallow sulfur doping. Interestingly, morphologies of MoO₃ can be controlled from 2D-blade to 1D-nanorod structures depending on the pressure and temperature in CVD furnace. Molybdenum oxides is well-known for good electron transfer path. But, MoO₃ is limited by poor HER stability. MoS₂ layers are not only good electrocatalyst for HER, but also prevent degradation of MoO₃ in acidic condition. In this study, we will discuss HER-catalytic performance of MoO₃/MoS₂ depending on two different morphologies of MoO₃ based on electrochemical analyses.

C.8.28
17:30
Authors : Yeong Don Park; Hwasung Lee
Affiliations : Department of Energy and Chemical Engineering, Incheon National University; Department of Chemical and Biological Engineering, Hanbat National University

Resume : A capillary pen drawing technique was developed as a new patterning methodology for the large-area patterning and fabrication of organic electronics. This approach provided several advantages over conventional approaches: the method was simple and versatile, there were no restrictions on the patterning shapes that could be produced, and the method could be tailored to a variety of substrates. Experimental results suggested several potential application directions for the site-selective patterning technique, including conductive text, electronic art, and electronic array connections. Our approach provides that capillary pen is a quite versatile method to fabricate the soluble organic patterns consisting of the semiconducting/conducting/insulting materials.

C.8.29
17:30
Authors : J.M. Dekkers, N. Hildenbrand, A. Janssens
Affiliations : Solmates BV, Drienerlolaan 5 (building 46), 7522 NB, Enschede, The Netherlands

Resume : It is well known that Pulsed Laser Deposition (PLD) is a very flexible and versatile technique allowing fast optimization of new and complex material thin films. Among these are Pb(Zr,Ti)O3, PMN-PT, BaTiO3, LiNbO3 and other materials of interest for applications in piezo-MEMS. Furthermore, the unique features of PLD allow for the integration of “Beyond Moore” materials in CMOS and new devices. Using Solmates PLD platform, such devices become now readily available for commercialization. The robust and reliable hardware allows uniform thin film deposition up to 200 mm diameter with high process reproducibility. The process can therefore be easily scaled towards as (pilot) production. In this contribution, the focus will be on wafer scale integration of Solmates new generation high performance PZT thin films. By interface engineering, we demonstrate the possible production of epitaxial piezo thin films on silicon wafers by means of TiN electrodes, buffer layers and nanosheets. Comparison to state of the art textured thin films will be shown. Excellent stability of the electrical and piezoelectric properties of those new films is shown and compared to the properties of state of the art textured PZT thin films grown on standard platinum.

C.8.30
17:30
Authors : Vilas S. Patil, Khushabu S. Agrawal and Ashok M. Mahajan
Affiliations : Department of Electronics, North Maharashtra University,Jalgaon

Resume : Nowadays Complementary Metal Oxide Semiconductor (CMOS) Technology demands low power consumption, faster speed performances of devices. Germanium has become again interesting channel material due to its higher (3 to 4 times) carrier mobilities than that of silicon. The main issue with germanium is its native oxide which is water soluble and chemically unstable. Effective passivation is required to overcome this issue. Various passivation techniques have been adopted by different groups on germanium surface such as sulphur passivation, nitride passivation, oxide passivation etc. Among these the nitride passivation is found effective to passivate germanium surface. Here, we are reporting the comparative study of effective passivation of N2 plasma and RTP-NH3. Wherein, we have used thermal and plasma treatment to passivate the germanium surface. NH3 and N2 gases are used for thermal and plasma nitride passivation, respectively. The effect of this passivation has been investigated on HfO2 thin films deposited on passivated germanium. The deposited films have been characterized physically by means of Ellipsometer and XPS. Ellipsometry shows the average thickness of HfO2 films near about 5 nm. Surface roughness has been studied by using AFM technique. To study the electrical properties Cr/Au metal contacts have been formed on both the films by using E- beam evaporator through shadow mask. The comparative study shows the improvement in electrical properties with N2 plasma over RTP-NH3 like, low hysteresis and effective oxide charges. The lower value of flat band voltage (0.22) has been observed for the devices passivated by using N2 plasma. The higher value of density of interface traps has been observed for N2 plasma passivated Ge MOS. The high power plasma (400 W) may be responsible for the high value of Dit and lower value of dielectric constant observed in this work. Keyword: Ge MOS, High-k, Passivation, N2 plasma, NH3 anneal.

C.8.31
17:30
Authors : JIŘÍ BURŠÍK, MILAN SVOBODA, IVO KUBĚNA, VILMA BURŠÍKOVÁ, PAVEL SOUČEK, LUKÁŠ ZÁBRANSKÝ, PETR VAŠINA
Affiliations : Institute of Physics of Materials, Academy of Sciences of the Czech Republic, Žižkova 22, 61662 Brno, Czech Republic; Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic

Resume : In the last decade, X-B-C (X=Mo, Ta, W) emerged as prospective candidates for protective hard coatings employed in cutting and forming applications. According to theoretical prediction and first experiments, these materials exhibit a high stiffness in combination with moderate ductility. In the present work nanostructured Mo-B-C coatings were prepared on WC-Co hard metal substrates by magnetron sputtering. The microstructure of deposited thin layers was studied by means of scanning and transmission electron microscopy on cross sections prepared using a focused ion beam. Both undisturbed layers and the volume under indentation prints were observed. The microstructure observations were correlated with mechanical properties characterized by means of nanoindentation experiments in both the static and the dynamic loading regime using a Berkovich indenter. Crack resistance was tested using indentation experiments with cube-corner indenter. Subsequent annealing of coatings caused elements redistribution and changes in phase constitution. Effect of the microstructure evolution on elastic modulus, indentation hardness and fracture resistance of the coatings is discussed. This research has been supported by the Czech Science Foundation (Project 15-17875S).

C.8.32
17:30
Authors : A.V. Shylo1, A.S. Doroshkevich1, 2, T.Yu. Zelenyak3, T.E. Konstantinova1
Affiliations : 1Donetsk Institute for Physics and Engineering NAS of Ukraine, 03680, Nauki ave, 46, Kyiv, Ukraine 2Joint Institute for Nuclear Research, 141980, str. Joliot-Curie, 6, Dubna, Russia, 3Dubna International University for Nature, Society and Man, 141980, Moscow region, Dubna, st. Universitetskay, 19

Resume : Keywords: zirconia, relative humidity, high pressure, electrochemical impedance spectroscopy, BET, compaction. Nanopowders based on zirconia are widely used in modern high technology. Along with the problem of synthesis of fine homogeneous powder, the problem of obtaining nanoceramics with high physical and mechanical properties from this powder is interesting too. Interparticle forces are prevent at nanopowders sealing. They are proportional to magnitude of surface energy of the system. Nanopowders based on zirconia have high chemical activity of surface. Thus, they can be able quickly change quantitative composition of hydration shell. Structural and thermodynamic energy states of the surface are changed too. Current task is to establish depending of sealing process of nanopowders by high hydrostatic pressure (HHP) from external physical conditions (temperature, humidity, atmospheric pressure). Checking of influence of initial conditions (relative humidity) at sealing process was the aim of this study. As the object of investigation compact sets from ZrO2 + 3% Y2O3 (700° C, 2h) nanopowder was used. Shrinkage, mass losses and specific surface area of samples(using BET-method) to determine the optimal degree of hydration were measured. In parallel, electrochemical impedance spectroscopy (EIS) studies were carried in order to determine dependence of the latter from surface hydration. Measurements of samples shrinkage showed that the maximum level of shrinkage after exposed by high hydrostatic pressure is reached at the level of ambient relative humidity is about 70 % Maximal mass losses of the system after pressure effects were detected at the same humidity. Analysis of BET-data showed that the lowest value of the specific surface area after compression of HHP is observed at 70 %. EIS-data showed that the electrical properties of the system are depending significantly from the ambient humidity. It is shown that humidity increasing from 39 to 94% leads to decreasing of the total resistance of the sample to 55 times (from 2.06MOhms to 37 kOhms). The possibility of establishing correspondence between parameters of electrical impedance and degree of hydration of nanopowders surface was concluded. Results indicate the need to stabilize external physical conditions during manufacturing operations with oxide nanopowders.

C.8.33
17:30
Authors : Adil Bouhadiche, Ameur Zegadi
Affiliations : Centre de Développement des Technologies Avancées, Unité de Recherche Composants et Dispositifs Optoélectroniques, Université de Sétif1 Campus El-Bez, 19000 Sétif, Algeria

Resume : Due to their specific properties, silicon nanocrystals (Si-nc) have recently attracted much interest for their use in silicon-based devices. However, controlling the formation of these nanocrystals (control of diameter and density) in high matrices (semiconductor or dielectric) remains incomplete. The simulation of the deposit and post-treatment steps is therefore necessary for designing the material with the required properties. In this context, this work consists of modeling the formation of silicon nanocrystals by Monte Carlo methods. First, in order to deduct the optimum deposition conditions allowing the obtain of a high density of amorphous silicon clusters and a controlled size, the deposition process of nitrogen doped silicon (SiNx) thin films obtained by a low-pressure chemical vapor deposition technique with a mixture of disilane (Si2H6) and ammonia (NH3) is simulated by using the kinetic Monte Carlo (KMC) method. A Part of this work is dedicated to the study of the formation of silicon nanocrystals in the presence of impurities in a SiNx matrix using the Monte Carlo (MC) method. Simulation results describe well the different stages of the silicon nanocrystal formation. Keywords : silicon nanocrystals, kinetic Monte Carlo, nitrogen doped silicon, silicon clusters, Monte Carlo simulation, crystal growth, crystallization kinetic, impurity distribution.

C.8.34
17:30
Authors : Anatoliy Titenko1, Lesya Demchenko2, Anatoliy Perekos3, Oleksandr Gerasimov3
Affiliations : 1 Institute of Magnetism, NAS and MES of Ukraine, Acad. Vernadsky Boulevard, 36-b, Kyiv, 03142, Ukraine 2 National Technical University of Ukraine "Kyiv Polytechnic Institute", Peremogy prospect, 37, Kyiv, 03056, Ukraine 3 G. V. Kurdyumov Institute for Metal Physics of the NAS of Ukraine, Acad. Vernadsky Boulevard, 36, Kyiv, 03142, Ukraine

Resume : Recently, an attention of researchers is focused on studying of functional materials with restructuring of martensitic-type in which a reversible changing in size under the influence of temperature, applied external stress, magnetic fields or combining them takes place and the effects of shape memory, pseudoelasticity (superelasticity), transformation plasticity, magnetoelastic deformation and etc. occur. Such materials find wide application as actuating mechanisms, actuators, sensors and others. Phase transformations of martensitic-type characterize the broad class of materials and alloys. Ageing Cu-Mn-Al alloys with original magnetic characteristics undergo thermo-induced martensitic transformation (MT) as well. Nowadays, such type of MTs which occur after solid solution decomposition with ferromagnetic nanoparticles precipitation in nonferromagnetic matrix attract interest. By thermal treatment, the system of ferromagnetic nano-dispersed particles in the nonferromagnetic matrix can be formed. Herewith, coherent nanoparticles precipitated during decomposition of high-temperature Cu-Al-Mn betta1-phase are coherently connected with matrix and do not undergo spontaneous MT at cooling. In this work, the influence of alloying with Mn as well as regimes of aging of high-temperature phase on subsequent martensitic transformation in Cu-Al-Mn alloy was studied. The morphology of martensitic transformation behaviour as a result of alloy aging under an annealing in a constant magnetic field with different sample orientation relatively to the field and without the field was investigated in order to directly control the process of martensite induction at cooling. The temperature dependences of electrical resistance, magnetic susceptibility, and the temperature and field dependences of magnetization were found. The alloys phase composition and microhardness were determined. The tendency of oriented growth of the precipitation phase particles in a direction of applied field and the increase of volume fraction of these particles under thermal magnetic treatment of material what favours a reversibility of induced martensitic transformation [1]. 1. A. Titenko, L. Demchenko. Effect of Annealing in Magnetic Field on Ferromagnetic Nanoparticle Formation in Cu-Al-Mn Alloy with Induced Martensite Transformation. Nanoscale Research Letters (2016) 11:237, DOI: 10.1186/s11671-016-1453-2

C.8.35
17:30
Authors : I.Kud, L.Yeremenko, L.Likhodid, M.Yakovleva, D.Zyatkevich
Affiliations : I.Kud, L.Yeremenko, L.Likhodid, M.Yakovleva, D.Zyatkevich Frantsevich Institute for Problems of Materials Science of NASU 3, Krzhyzhanovsky St., Kiev, 03142, Ukraine

Resume : The influence of mechanical activation on the mechanism of formation of a Ti–Al–Cr alloy has been investigated. Titanium aluminides have aroused considerable interest due to their high heat resistance, high-temperature strength, oxidation resistance, and low density. The indicated properties make them promising materials for the development of protective coatings instead of nickel refractory alloys, used in aerospace engineering. These coatings make it possible to raise substantially the working temperatures of products without changes in the mechanical properties of the substrate, i.e., titanium alloys. On the other hand, low ductility and poor formability restrict considerably their industrial application. A great effort has been devoted to improve the properties of Ti–Al alloys by means of chemistry modification. Mechanical alloying is exploited to produce aluminum–titanium alloys with additional dispersoids. Low-temperature solid-state reaction (SSR), which can be originated in binary or ternary systems by improving a severe plastic deformation as in the case of high-energy ball milling, has been investigated. This may lead to the formation of equilibrium intermetallic compounds. The method of deposition of a protective coating determines requirements to its material. For the detonation-gas method, important factors are morphology and particle-size distribution of sprayed powder, which influence its flowability. It is desirable to obtain spherical particles with a size of 40–60 μm. The optimal regime of mechanical treatment of the initial powders, which provides the beginning of phase formation and accumulation of the sufficient amount of energy for the substantial acceleration of the subsequent process of solid-state synthesis in vacuum in the self-propagating high-temperature mode, has been established. This regime is accompanied by a substantial decreases in the temperatures of beginning and completion of synthesis (below the melting point of aluminum) and provides the formation of intermetallic spherical powders with a mean particle size under 60 μm, which do not require subsequent milling. The investigated protective coatings from the prepared Ti–Al–Cr intermetallic powder sprayed by the detonation method on titanium alloys raise the operating temperature of products up to 1173 K. In this case, the weight gain during oxidation in air decreases by a factor of 2. It has been established that the alloying of titanium aluminide by chromium enhances the heat resistance and fracture toughness of the coatings. A substantial increase in the hardness of the coatings as compared to that of detonation coatings based on γ-TiAl (11 GPa and 5 GPa, respectively) has been achieved. The increased working characteristics make it possible to use the Ti–Al–Cr intermetallic compound in the aerospace industry.

C.8.36
17:30
Authors : Karol Załęski 1, Emerson Coy 1, Hubert Głowiński 2, Janusz Dubowik 2, Hans-Peter Schönherr 3, Jens Herfort 3
Affiliations : 1 NanoBioMedical Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland; 2 Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Poznań, Poland; 3 Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, D-10117 Berlin, Germany;

Resume : Thin films of Co2FeSi(111) were grown at 200˚C using molecular beam epitaxy on InAs(111) substrates and characterized by structural and magnetic methods. X-ray analysis showed that the films exhibit L21 structure, while pole figures along the [220] direction, showed a 30˚ in-plane rotation respect to the [220] direction of the InAs substrate. The magnetic moment with the value of 1040 ±60 emu/cm3 is in good agreement with the value of the bulk Co2FeSi at room temperature. On the other hand, weak uniaxial anisotropy in the film plane can indicate on the stress induced by the lattice constants mismatch between the film and the substrate. Overall, the results suggest that Co2FeSi can be used as a highly spin-polarized ferromagnetic spin injector and detector in InAs-based spintronic devices. K.Z. acknowledges support from Polish National Science Center Grant DEC-2014/15/B/ST3/02927.

C.8.37
17:30
Authors : A. P. Gertych, K. Czerniak, K. Żerańska, A. Dużyńska, M. Zdrojek and J. Judek.
Affiliations : Faculty of Physics, Warsaw University of Technology, Koszykowa 75, 00-662 Warsaw, Poland

Resume : Uniqe and often desired properties of both single- and multi-walled carbon nanotubes can be utilised in many ways. One strategy is based on use of individual nanoobjects in the fabrication of, e.g., nanotransistors, another approach employs properties of an assemblage of nanotubes which can form, e.g., a thin film or composite with other materials. In our work we focus on discrete nature of carbon nanotube thin films that implies intrinsic inhomogenity at the nanoscale. To study the thermal properties of single walled carbon nanotubes thin films we use microRaman spectroscopy, a contactless technique with spatial resolution below 1μm. Phonon energies, including their dependencies on the temperature or the laser power, which further enables calculation of the thermal conductivity or interface conductance are investigated in a statistical approach. We present useful methodology for proper handling the heating effects both from laser illumination and heating stage (zero laser power limit). We also demonstrate that the 2D phonon energy derivatives both in respect to the temperature χT or laser power χP have a gaussian distribution which does not originate in the uncertainty of a single measurement but in intrinsic inhomogenity of the sample. For instance, the mean value of χT, acquired from a 30μm x 30μm area, step 3μ, equals -0.036 cm-1/K and standard deviation is 0.0074 cm-1/K. At the end thermal conductivity and total interface conductance of semiconducting, metalic and mixed carbon nanotubes thin films are extracted using an partial differential equation systems.

C.8.38
17:30
Authors : M. Advand, M. Ganjian, M. Kolahdouz*, B. A. Ganji, M. Norouzi
Affiliations : Department of Electrical and Computer Engineering, University of Tehran, Tehran, Iran Department of Electrical and Computer Engineering, Babol Noshirvani University of Technology, Babol, Iran * Corresponding Author: kolahdouz@ut.ac.ir

Resume : Many diseases can be detected from presence of a special specie in a specified quantity of the human exhales. Therefore, sensing exhale gases can be a powerful method of disease diagnosis. For this purpose, field emission (FE) mechanism can be used in high accuracy exhale bio sensors. Recently, ZnO nanorods FE has attracted so much attention because of ZnO exclusive specifications. One of the most important factors in attaining a privileged FE performance from a nanorod array is the array?s resistance and its electron concentration. Thus, Cds nanoparticles deposited on the Aluminum-doped ZnO nanorods can absorb light and generate electron-hole pairs. The generated electron in the presence of light in the thin CdS layer will transfer to ZnO and will positively affect the FE properties. The standard CMOS processing on the glass substrate has been used for the sensor fabrication. 2% AL-doped ZnO sputtering has been used for the seed layer and the array of nanorods was in-situ doped using hydrothermal process. The quantum dots were epitaxially deposited using successive ionic layer adsorption and reaction (SILAR) at room temperature. The morphology of the grown arrays was controlled using top and cross-sectional field emission electron microscopy images. The crystalline quality of all doped samples was investigated using photoluminescence and x-ray diffraction. Finally, the IV curves and field emission responses were measured by Keithley-K361 parameter analyzer to estimate the impact of doping and presence of CdS nanolayer on the electrical response.

C.8.39
17:30
Authors : E. S. Bronze-Uhle,1,2 B. C. Costa,1 V. F. Ximenes1 and P. L. Lisboa-Filho 1,2
Affiliations : 1 UNESP - Univ Estadual Paulista, POSMAT - Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, Bauru, SP, Brazil 2 DF-FC, UNESP - Univ Estadual Paulista, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru, SP, Brazil.

Resume : Bovine Serum Albumin (BSA) is highly water soluble and binds noncovalently with drugs or an inorganic material for the efficient drug delivery in various areas the affected body. Historically, albumin has been extensively applied as biodegradable anti-cancer drug charger because of its excellent biocompatibility and high stability in blood can accumulate in malignant or inflamed tissue. Due to the well defined structure of the protein, containing charged amino acids, the albumin nanoparticles may allow electrostatic adsorption molecules negatively or positively charged without the application of other compounds on the surface. Therefore significant amounts of drug can be incorporated within the particle, as a function of different albumin binding sites. In this work we study the synthesis of bovine serum albumin nanoparticles, by desolvation process, containing apocynin as the active agent. Apocynin acts to inhibit NADPH oxidase (NOX) and it has been used as one of the most promising drugs in experimental models of inflammatory and neurodegenerative diseases. Apocynin is a cheap substance and can be obtained commercially from various companies, which facilitates broad application of this phytochemical.To this end, in synthetic procedure, the pH synthesis (7.4 and 9.0) in order to evaluate the influence on the size and stability of the formed nanoparticles. The samples were analyzed using SEM, TEM, AFM, FTIR, UV-Vis and fluorescence. The results demonstrate the obtaining albumin nanoparticles interacting with apocynin but nevertheless failed to set only if they are adsorbed or encapsulated in the protein nanoparticles.

C.8.40
17:30
Authors : Aparna Zagabathuni, shyamal kumar pabi, sudipto ghosh
Affiliations : Indian Institute of Technology Kharagpur; Indian Institute of Technology Kharagpur; Indian Institute of Technology Kharagpur

Resume : The thermal conductivity measured and reported by different investigators using transient hot-wire technique shows wide diversity, and the present paper reports for the first time that the container materials used for such measurements is one of the factors leading to this variation. Ultra-fine silver nanoparticles were prepared by a simple chemical reduction method. The as-prepared Ag nanoparticles were characterized by X-ray diffraction analysis, transmission electron microscopy, and fourier transform infrared spectroscopy. From the dynamic light scattering, it was found that the size of the Ag nanoparticles ranged from 6-30 nm, with an average size of 13 nm. Programmed ultrasonication has been carried out for the preparation of the aqueous silver nanofluid. This silver nanofluid was stable for more than a month at neutral pH. To check the distribution of silver nanoparticles in the aqueous silver nanofluid, atomic absorption spectroscopy has been carried out by carefully collecting a small amount of nanofluid samples from various locations in a stainless steel and a polypropylene container. A non-uniform distribution of Ag nanoparticles was observed when the nanofluid was in stainless steel container apparently due to the charge accumulation on the metallic surface, whereas in the polypropylene container the Ag nanoparticles in the nanofluid were found to be evenly distributed. The thermal conductivity of aqueous silver nanofluid in polypropylene and stainless steel containers at different locations have been measured by means of a needle like probe of the KD2 device. It has been observed that the thermal conductivity of silver nanofluid is high near to the stainless steel container wall and less at the centre of the container, whereas in the polypropylene container the conductivity is same everywhere. This novel phenomenon can be explained by the collision mediated model for thermal conductivity enhancement of nanofluids recently formulated by the present school. Their model points out that pulse-like rapid heat transfer in few pico seconds occur during frequent collision of the nanoparticles like Ag with the heat source in the course of the Brownian motion of particles in the nanofluids. This is followed by dissipation of the acquired heat by the nanoparticles to the surrounding fluid during their subsequent Brownian motion that would make a significant contribution to the thermal conductivity enhancement.

C.8.41
17:30
Authors : M. Jankowski (1), D.M. Kaminski (2), K.H. Vergeer (3), M. Mirolo (1), F. Carla (1), G. Rijnders (3), T.R.J. Bollmann (3)*
Affiliations : (1) ESRF-The European Synchrotron, 71 Avenue des Martyrs, Grenoble, France (2) Department of Chemistry, University of Life Sciences in Lublin, 20-950 Lublin, Poland (3) University of Twente, Inorganic Materials Science, MESA Institute for Nanotechnology, P.O. Box 217, NL-7500AE Enschede, The Netherlands

Resume : Nanostructured ultrathin bismuth films [1,2] have attracted a lot of interest as they reveal exotic functional properties that do not exist in bulk. The material properties are advantageous for the realization of e.g. spin based electronic devices, magnetoresistance effects and topological properties. Therefore nanosized Bi structures grown at different orientations have high potential for both fundamental research and technological applications. Especially growth on an atomically well defined insulating substrate, providing an infinite potential well barrier, is essential for future electronic applications as well as to get a deeper understanding of its controllability. In this study we demonstrate by Surface X-ray Diffraction (SXRD) the controlled growth of thin Bi(110) and Bi(111) films on such a substrate: atomically smooth insulating sapphire (α-Al2O3(0001)). The preparation of (110)-oriented Bi films, a rather exotic orientation, is a difficult task. At temperatures as low as 40K, we are able to slow down kinetics and thereby controlling the growth of Bi towards Bi(110), stable up to 400K. By annealing the Bi(110) films beyond, they can be transformed towards stable Bi(111) films. For films grown around RT, thin films grow in (110) orientation, followed by growth in (111) orientation. At elevated temperatures, Bi crystallizes in hexagonal (111) orientation on sapphire, having a lattice misfit of 4.6% similar as it does on a wide variety of other substrates [3-7]. * corresponding author: t.r.j.bollmann@utwente.nl References [1] E.I. Rogacheva, et al. Appl. Phys. Lett. 82, 2628 (2003). [2] Y.W. Wang, et al. Appl. Phys. Lett. 88, 143106 (2006). [3] H. Hattab, et al. Thin Solid Films 516, 8227 (2008). [4] M. Kammler, et al. Surface Science 576, 56 (2005). [5] F. Song, ACS Appl. Mater. Interfaces, 7, 8525 (2015). [6] G. Bian, et al. ACS Nano, 10, 3859 (2016). [7] M.-Y. Yao, et al. Scientific Reports 6, 21326 (2016).

C.8.42
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12:30 Lunch break    
 
Common Session with symposia M & Z : C. Richard A. Catlow, Andrea Illiberi, Duncan Allsopp
14:00
Authors : Hideo Hosono
Affiliations : Tokyo Institute of Technology

Resume : Creating novel functionality utilizing abundant element is a major challenge in material research. 12CaO?7Al2O3(C12A7) with a crystal structure composed of 3D-connected sub-nanometer-sized cages entrapping oxygen ions as the counter anion is an insulator with a band gap of ~7eV. We have attempted to realize novel functionalities by replacing these oxygen ions with unconventional anions such as O-, H- and electron. C12A7:O- and C12A7:H- exhibit high oxidation power enough to oxidize Pt and light-induced insulator-electronic conductor conversion, respectively. The striking results were obtained for C12A7:e-, a first RT electride ; the conductivity at RT is changed from ~E-10 to E+3 Scm-1 and metal-superconductor transition occurs at low temperatures. The most unique property is its low work function of 2.4eV, comparable to metal potassium, but chemically stable. This property led to the finding of high performance catalyst for ammonia synthesis at ambient pressure when Ru nanoparticles are loaded on the surface of C12A7:e-. A series of finding on electro-active functionality in C12A7 demonstrated the power of nanostructure composed of abundant elements and may be regarded as a pioneering research of ?Element Strategy Initiative?, a Japan-original science and technology project. We expect the recent discovery of 2D-electride Ca2N and Y2C along with material design concept would open a new frontier. Recently, we have created amorphous C12A7:e thin films by sputtering. The resulting thin films are optically transparent but retain a low work function (~3.0eV). Such a unique properties meet the requirement for electron injection layers of inverted-type OLEDs. In this talk I show the recent advances in science and application of C12A7:e along with the background.

C.CMZ.1
14:45
Authors : Christina Scheu
Affiliations : Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany

Resume : Within the last years several concepts were developed for creating environmentally friendly energy sources, such as photovoltaics, fuel cells, and photo-electrochemical cells, which are based on novel nanostructured morphologies and material combinations. For these energy conversion systems semiconducting oxide nanostructures are of great interest since they can be used as e.g. electrode materials or photocatalysts. The occurring interfaces and defects within the nanostructures are the key parameters which determine the functionality and limit charge carrier separation and charge transport. To improve the performance, the inorganic nanostructures can be modified by e.g. doping and/or by creating core-shell structures. Annealing treatments can be performed to minimize defects and to induce phase transformation leading to crystal modifications with a more suitable band gap. Two examples will be presented in this talk, Nb3O7(OH) [1] and TiO2 [2,3] nanowire arrays which can be applied as electrode material in dye sensitized hybrid solar cells and in light induced water-splitting devices. The nanostructures were synthesized hydrothermally. Different advanced transmission electron microscopy (TEM) techniques were applied to study the crystal structure, atomic arrangement, chemical composition, bonding behavior and band gap of the individual nanowires and networks on the atomic scale The results were correlated to the synthesis conditions and used to construct growth models. In addition, the functional properties of the Nb3O7(OH) and TiO2 nanostructures were measured in photo-electrochemical and dye sensitized hybrid solar cells. The properties like charge carrier mobility and lifetime were evaluated and further improved by using modified systems developed with the insights obtained by TEM [3]. [1] S. B. Betzler, A. Wisnet, B. Breitbach, C. Mitterbauer, J. Weickert, L. Schmidt-Mende, and C. Scheu, J. Mater. Chem. A, 2014, 2, 12005 [2] A. Wisnet, S. B. Betzler, R. V. Zucker, J. A. Dorman, P. Wagatha, S. Matich, E.Okunishi, L. Schmidt-Mende, and C. Scheu, Cryst. Growth & Design, 2014, 14(9), 4658. [3] A. Wisnet, K. Bader, S. B. Betzler, M. Handloser, J. Weickert, A. Hartschuh, L. Schmidt-Mende, C. Scheu, J. A. Dorman., Adv. Funct. Mater., 2015, 25, 2601. [4] The author would like to thank the colleagues and co-workers who contributed to this work and the German Research Foundation (DFG) for financial support.

C.CMZ.2
14:45
Authors : Christina Scheu
Affiliations : Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany

Resume : Within the last years several concepts were developed for creating environmentally friendly energy sources, such as photovoltaics, fuel cells, and photo-electrochemical cells, which are based on novel nanostructured morphologies and material combinations. For these energy conversion systems semiconducting oxide nanostructures are of great interest since they can be used as e.g. electrode materials or photocatalysts. The occurring interfaces and defects within the nanostructures are the key parameters which determine the functionality and limit charge carrier separation and charge transport. To improve the performance, the inorganic nanostructures can be modified by e.g. doping and/or by creating core-shell structures. Annealing treatments can be performed to minimize defects and to induce phase transformation leading to crystal modifications with a more suitable band gap. Two examples will be presented in this talk, Nb3O7(OH) [1] and TiO2 [2,3] nanowire arrays which can be applied as electrode material in dye sensitized hybrid solar cells and in light induced water-splitting devices. The nanostructures were synthesized hydrothermally. Different advanced transmission electron microscopy (TEM) techniques were applied to study the crystal structure, atomic arrangement, chemical composition, bonding behavior and band gap of the individual nanowires and networks on the atomic scale The results were correlated to the synthesis conditions and used to construct growth models. In addition, the functional properties of the Nb3O7(OH) and TiO2 nanostructures were measured in photo-electrochemical and dye sensitized hybrid solar cells. The properties like charge carrier mobility and lifetime were evaluated and further improved by using modified systems developed with the insights obtained by TEM [3]. [1] S. B. Betzler, A. Wisnet, B. Breitbach, C. Mitterbauer, J. Weickert, L. Schmidt-Mende, and C. Scheu, J. Mater. Chem. A, 2014, 2, 12005 [2] A. Wisnet, S. B. Betzler, R. V. Zucker, J. A. Dorman, P. Wagatha, S. Matich, E.Okunishi, L. Schmidt-Mende, and C. Scheu, Cryst. Growth & Design, 2014, 14(9), 4658. [3] A. Wisnet, K. Bader, S. B. Betzler, M. Handloser, J. Weickert, A. Hartschuh, L. Schmidt-Mende, C. Scheu, J. A. Dorman., Adv. Funct. Mater., 2015, 25, 2601. [4] The author would like to thank the colleagues and co-workers who contributed to this work and the German Research Foundation (DFG) for financial support.

C.CMZ.2
15:30 Coffee break    
16:00
Authors : Chris G. Van de Walle
Affiliations : Materials Department, University of California, Santa Barbara, California, USA

Resume : Perovskite oxides have received significant attention in recent years, in part due to their ability to generate very high density two-dimensional electron gases (2DEGs) at interfaces between polar and nonpolar materials [1]. Most of these complex oxides have degenerate conduction bands composed of transition-metal d states, leading to large effective masses and low mobilities, a detriment for electronic applications. BaSnO3 has emerged as an alternative: it crystallizes in the perovskite structure but its conduction band is nondegenerate and composed of Sn s states, resulting in high mobility, favorable for a transparent conductor. I will show how cutting-edge first-principles calculations shed light on the multiple aspects of this problem: band alignment and confinement of the 2DEG [1,2], mobility [3], and for applications requiring transparency, fundamental limits on absorption [4]. Work performed in collaboration with B. Himmetoglu, A. Janotti, E. Kioupakis, K. Krishnaswamy, and H. Peelaers, and supported by ONR, DOE, LEAST, and NSF. [1] L. Bjaalie, B. Himmetoglu, L. Weston, A. Janotti and C. G. Van de Walle, New J. Phys. 16, 025005 (2014). [2] K. Krishnaswamy, L. Bjaalie, B. Himmetoglu, A. Janotti, L. Gordon, and C. G. Van de Walle, Appl. Phys. Lett. 108, 083501 (2016). [3] B. Himmetoglu, A. Janotti, H. Peelaers, A. Alkauskas, and C. G. Van de Walle, Phys. Rev. B 90, 241204(R) (2014). [4] H. Peelaers, E. Kioupakis, and C.G. Van de Walle, Phys. Rev. B 92, 235201 (2015).

C.CMZ.3
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Nanomaterials for catalysis : -
09:00
Authors : Paula Cruz, Yolanda Pérez, Isabel del Hierro, Sanjiv Prashar,Santiago Gómez-Ruiz
Affiliations : Departamento de Biología y Geología, Física y Química Inorgánica, Calle Tulipán s/n, E-28933, Móstoles (Madrid), Spain

Resume : Catalytic and photocatalytic reactions are crucial in various transformations for different applications in Chemistry. However, most of the catalysts used for these reactions, based on homogeneous systems, are expensive, inefficient or need very high quantities of solvent resulting in non-sustainable systems. In this context, our work is focused on the synthesis, characterization and study of the catalytic properties of novel nanomaterials based on immobilized catalytic species such as metal complexes, metal nanoparticles or metal oxide nanoparticles on solid high-surface-area nanostructured materials. In addition, we are developing novel methods for the preparation of nanoparticles stabilized by protective agents that prevent aggregation and enhance the effectiveness and applicability of these heterogeneous systems in a wide variety of catalytic applications such as catalytic oxidation of benzyl alcohol, polymerization of polar monomers, C-C formation via Suzuki-Miyaura coupling reactions, photocatalytic degradation of contaminants in water under visible light and photocatalytic formation of hydrogen via methanol photoreforming. In this communication, the most recent results of our group will be described, emphasizing key factors such as the use of environmentally friendly reagents, utilization of ionic liquids, improvement of the recyclability of the catalytic nanosystems and improving their sustainability.

C.9.1
09:30
Authors : Mariano Garcia-Soto, Carlo Gonzato, Karsten Haupt
Affiliations : Sorbonne Universités - Université de Technologie de Compiègne, CNRS Laboratory for Enzyme and Cell Engineering CS 60319, 60203 Compiègne Cedex, France.

Resume : We present here the design and synthesis of organic-inorganic nanocomposite materials consisting of a molecularly imprinted polymer (MIP), for specific target recognition, and gold nanoparticles (GNP), for optical detection and photothermal heating, with potential applications in bioimaging and theranostics. MIPs are synthetic antibody mimics that specifically recognize molecular targets. They are highly cross-linked polymers made with functional monomers in the presence of the target molecule acting as template. This interaction renders three-dimensional binding sites in the polymer that are complementary to the template molecule in terms of size, shape, and chemical functionality. GNP display intense colorations in the visible spectrum that make them attractive as platforms for sensing. Their localized surface plasmon resonance (LSPR) is due to the interaction of the metal conduction electrons with light. GNP can be designed to absorb more light than scatter it, with any excess energy released as heat in the vicinity of their surface. We have used the heat generated by these GNP upon irradiation with light to initiate thermally-induced free-radical polymerizations around individual particles. This results in the red-shift and broadening of the LSPR, with polymer coatings that can develop into large networks when the irradiation is prolonged. This polymer shell can be used to modify the surface properties of the particle and for molecular recognition when the polymer is a MIP.

C.9.2
09:50
Authors : Jorge Tovar Rodriguez, Jose Gonzalez Rivera, Carlo Ferrari, Iginio Longo, Emiliano Fratini, Piero Baglioni
Affiliations : Università degli Studi di Firenze e CSGI; Università di Pisa; Istituto Nazionale di Ottica - Consiglio Nazionale delle Ricerche

Resume : In this work, we present a novel integrated green synthesis of self-assembled mesoporous silicon-based sieves using a geothermal waste as silicon source. Hydrothermal synthesis was performed using both conventional heating and a coaxial antenna for in-situ microwaves (MW) irradiation . A series of surfactant-templated hexagonally-ordered mesoporous materials were successfully obtained avoiding the use of toxic reagents like alkoxides, colloidal or fumed silicas. All prepared materials exhibit hexagonal structure, narrow pore size distribution, high surface areas and were used as catalytic supports for a Zn active phase. The catalytic activity of these materials was evaluated in a fast and eco-friendly heterogeneous catalytic process to valorize glycerol into a glycerol carbonate using microwaves irradiation for thermal activation. The use of Zn/mesoporous silica derived from the cheap silicon waste precursor and the fast MW processing featured similar catalytic properties than those obtained using the mesoporous material synthesized through the traditional approach. The reaction conditions to yield glycerol carbonate via the urea route, such as temperature, reaction time, and the catalyst dosage were explored. The proposed MW assisted methodology resulted in a high glycerol conversion, high selectivity towards glycerol carbonate and short reaction processing. The synergy between the MW technology and the low cost of the heterogeneous catalyst in the integrated MW-assisted process leads to a promising, environmentally friendly, easily scalable-up and cheap approach to glycerol carbonate production.

C.9.3
10:10
Authors : Stefano di Stasio
Affiliations : CNR-IM Italian National Research Council - Istituto Motori Nanostructures, Ligt Scattering and X-ray Techniques Laboratory, Via Marconi 8 - I-80125 Napoli, Italy

Resume : In the following paper we will discuss in brief the results, which we obtained in our laboratory at CNR the last years, about the synthesis of metal nanoparticles (NPs), to be used in the sensing application. Here we make focus on Zinc NPs produced in an inert gas flushing in a quartz reactor (aerosol route) via an evaporation-condensation process. Afterwards, we cope the task of realize a prototype of pollutants gas sensor and compare the electrical responses of three zinc powders, at parity of constituting species, but with different shape and aggregate morphology, that are isolated primary or partially coalesced nanoparticles, aggregates and hollow nanofibers or nanotubes. All the three type of samples (isolated nanoparticles, aggregates and nanotubes) are subjected to a slight surface oxidation off line at 200 °C for one hour, in a way to form core-shell nanostructures with an external 50 Å thick layer of ZnO over the inner Zn core matter. Evidence is given about the fact that a sample constituted by Zn-ZnO nanotubes with about 400 Å diameter, produces an electrical response to the test gas NO2, which is 10^4 times the response of the bulk Zinc-ZnO. An explanation is proposed on the basis of Diffusion Reflectance Fourier Transformed Infra Red spectrometry (DRFTIR) of the same sample via the so-called Oxygen Pseudo-Defects theory.

C.2.3
10:30 Coffee break    
 
Nanomaterials: synthesis and applications : -
11:00
Authors : Vladimir Poborchii1, Hiroyuki Ishii 1, Hiroyuki Hattori 1, Wen-Hsin Chang 1, Tetsuya Tada1, Pavel I. Geshev2 and Tatsuro Maeda1
Affiliations : 1 Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, AIST Central-5, Tsukuba 305-8565, Japan 2 Institute of Thermophysics of the Russian Academy of Sciences, Lavrentyev Ave. 1, and Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russia

Resume : We fabricated Ge-on-insulator (GOI) monocrystalline layers with thickness H = 1 – 18 nm using high quality heteroepitaxial growth and Ge layer transfer with epitaxial lift-off technique on fused SiO2 substrate. We study GOI Raman and optical reflection/transmission/absorption spectra. With a decrease in H, we observe electron-confinement-induced blue shift of L-point direct-band-gap absorption peak. Raman spectra display longitudinal optical (LO) phonon and low-frequency confined acoustic phonon bands. For H < 5 nm, additional very weak bands due to insignificant amorphous inclusions appear in the spectra. In accordance with the wave-vector-quantization theory, acoustic phonon frequencies show ~1/H dependence at H > 5 nm. However, for H < 5 nm, we observe deviation from the ~1/H law suggesting a change in GOI mechanical properties or a change from discrete to continuum mode Raman activity. For H > 12 nm, LO phonon Raman band shows slight broadening and upshift compared to bulk Ge. With a decrease in H, the band displays enhancement and downshift. Also as H decreases, the band homogeneously broadens proportionally to 1/H. We attribute these findings to a reduction in reflectance plus electron confinement, thickness-dependent stress (compressive for H > 12 nm and tensile for H < 12 nm) and surface-disorder-induced phonon lifetime reduction. Contrary to the Richter-Campbell-Fauchet optical phonon confinement model, wave-vector-relaxation-induced LO phonon Raman band asymmetric broadening is shown to be negligible. We also observe strong laser-induced GOI heating suggesting extremely low thermal conductivity.

C.10.1
11:15
Authors : Roman Anufriev (1); Aymeric Ramiere (1,2); Jeremie Maire (1); Masahiro Nomura (1,3,4)
Affiliations : (1) Institute of Industrial Science, the University of Tokyo, Tokyo, 153–8505, Japan (2) Laboratory for Integrated Micro Mechatronic Systems/National Center for Scientific Research-Institute of Industrial Science (LIMMS/CNRS-IIS), the University of Tokyo, Tokyo, 153–8505, Japan (3) Institute for Nano Quantum Information Electronics, the University of Tokyo, Tokyo, 153–8505, Japan (4) PRESTO, Japan Science and Technology Agency, Saitama, 332–0012, Japan

Resume : Recently, ballistic heat transport has been demonstrated experimentally various nanostructures, but a practical use of this phenomenon remained challenging, as thermal phonons tend to travel in almost random directions. We used micro-TDTR experiments and Monte-Carlo (MC) simulations to show the in-plane ballistic heat transport with well-defined directionality in phononic nanostructures and a possibility to use this phenomenon for heat guiding and focusing. First, we studied heat transport in silicon thin films with aligned and staggered periodic arrays of holes, and demonstrated that significant difference in thermal conductance appears when the characteristic size of the structures becomes smaller than 100 nm. The difference in thermal conductance is attributed to ballistic phonon transport in the structures with the aligned lattice. Next, we demonstrated that these structures can be used to guide the phonons and act at a source of ballistic heat emission in solids. This emission was couples into nanowires, where the ballistic path of the phonons was continued, and corresponding nanowire length and temperature dependences were observed. Finally, we used this concept to create thermal lens nanostructures which can focus thermal energy in the focal point. Our theoretical and experimental results suggest that the created hot-spot is smaller than 200 nm in diameter, and thus can be used in biomedicine, thermoelectrics and wherever selective heating is required.

C.10.2
11:30
Authors : Ilknur Eryilmaz, John Mohanraj, Alessandro Fraleoni Morgera*
Affiliations : Dept. of Engineering and Architecture, University of Trieste

Resume : Recently we reported over a novel wet-processing method able to deliver in minutes nanofibers over large areas, effective on both polymers and carbon nanotubes, termed ASB-SANS (Auxiliary Solvent-Based-Sublimation Aided NanoStructuring) [A. Fraleoni Morgera, Small, 2011, 7, 321-325; A. Fraleoni Morgera et al., RSC Adv., 2013, 3, 15664–15669]. Here we show how it is possible to control the transition from continuous fibers to aligned dots simply changing the composition of the ternary solution (TS) on which ASB-SANS is based. A ternary diagram relating the various TS compositions and the resulting nanopatterns morphologies has been realized. The nanopatterns (fibers/aligned dots) width and inter-pattern distance variations have been analyzed with respect to the TS composition, showing consistency with currently accepted models for macromolecular chains mobility in a medium. In line with these observations, a tentative explanation of the mechanisms underlying the patterns formation is given.

C.10.3
11:45
Authors : Katrin Schulz1, Roman Schmack1, Anke Kabelitz2, Franziska Emmerling2, Ralph Kraehnert1
Affiliations : Katrin Schulz1, Roman Schmack1, Ralph Kraehnert1: 1Department of Chemistry, Technical University Berlin, Berlin, Germany; Anke Kabelitz2, Franziska Emmerling2: 2BAM Federal Institute for Materials Research and Testing, Berlin, Germany

Resume : Mesoporous films of nanocrystalline hematite (α-Fe2O3) show unique properties for applications as electrode material in the field of renewable energy research, e.g. as photoanode for electrochemical water splitting. The performance of iron oxide films in these applications is critically influenced by the material’s phase composition, crystallinity and porosity. We present a comprehensive investigation of the crystallization process of mesoporous ferrihydrite to hematite and deduce guidelines for improved structural control. Films of ferrihydrite on silicon were obtained via soft templating of mesopores with amphiphilic block-copolymer PEO-PB-PEO and iron nitrate as metal oxide precursor. The parameters of the subsequent thermal treatment were systematically varied in a wide range of conditions to assess the influence of temperature, time, gas atmosphere and humidity on the transformation. Physicochemical characterization techniques, particularly SEM, but also TEM, SAXS, SAED and XRD were applied to characterize the evolution of crystallinity, porosity and phase composition during the transformation. The present contribution investigates qualitatively and quantitatively the transformation of ferrihydrite to hematite by elucidating the nucleation rate of hematite, the nucleation mechanism and the activation energy of the phase transformation. Compared to bulk characterization methods we show the advantage of SEM characterization to investigate phase transformation on a nm scale.

C.10.4
12:00
Authors : V. Elofsson*, G.A. Almyras*, B. Lü*, R.D. Boyd**, K. Sarakinos*
Affiliations : *Nanoscale Engineering Division, Department of Physics, Chemistry and Biology, Linköping University, SE-58183, Linköping, Sweden; **Plasma and Coatings Physics Division, Department of Physics, Chemistry and Biology, Linköping University, SE-58183, Linköping, Sweden

Resume : Physical attributes of multicomponent materials of a given chemical composition are determined by atomic arrangement at property-relevant length scales. A potential route to access a vast array of atomic configurations for material property tuning is by synthesis of multicomponent thin films using vapor fluxes with their deposition pattern modulated in the sub-monolayer regime. However, the applicability of this route for creating new functional materials is impeded by the fact that a fundamental understanding of the combined effect of sub-monolayer flux modulation, kinetics and thermodynamics on atomic arrangement is not available in the literature. Here we present a research strategy and verify its viability for addressing the aforementioned gap in knowledge. This strategy encompasses thin film synthesis using a route that generates multi-atomic fluxes with sub-monolayer resolution and precision over a wide range of experimental conditions, deterministic growth simulations and nanoscale microstructural probes. Investigations are focused on structure formation within the archetype immiscible Ag-Cu binary system, revealing that atomic arrangement at different length scales is governed by the arrival pattern of the film forming species, in conjunction with diffusion of near-surface Ag atoms to encapsulate 3D Cu islands growing on 2D Ag layers. The knowledge generated and the methodology presented herein provides the scientific foundation for tailoring atomic arrangement and physical properties in a wide range of miscible and immiscible multinary systems.

C.10.5
12:15
Authors : Anastasiia Y. Nimets, Klaus Schuenemann, Dmytro M. Vavriv
Affiliations : Anastasiia Y. Nimets, Klaus Schuenemann, Institute of High-Frequency Technology, Hamburg University of Technology, 22 Denickestrasse, 21073 Hamburg, Germany; Anastasiia Y. Nimets, Dmytro M. Vavriv, Department of Microwave Electronics, Institute of Radio Astronomy of NAS of Ukraine, 4 Chervonopraporna Str., 61002 Kharkov, Ukraine

Resume : Nanomechanical resonators (NMRs) are now considered as promising candidates for a number of applications, including sensors, filters, switches, and memory elements. The resonant excitation of mechanical vibrations in a beam is the main phenomenon used when developing such devices. Typically, a two-frequency resonance with the driving frequency close to the natural frequency of the beam is exploited. However, such excitation does not provide a convenient possibility for controlling the central frequency of the resonance, its linear dynamic range, and the critical value for the bistability onset what is, however, needed for the applications. Some approaches, like for example, bending of a nanoresonator beam or introducing a gate to control the beam vibrations electrostatically, have formerly been proposed to meet this demand. In this paper, we demonstrate that there is a relatively simple solution to this problem that is based on adding a low-frequency (LF) spectral component to the high-frequency (HF) drive. The beam geometric nonlinearity provides an interaction of these frequencies and a formation of three-frequency resonances. The parameters of these resonances are easily and reversibly controlled by varying the amplitude and the current of the LF driving. In particular, it is possible to increase essentially the linear dynamical range of the resonator by decreasing the current amplitude. This feature can be of interest for various sensor applications. An increase of this amplitude results in lowering the threshold for bistability with respect to the HF driving. This is obviously attractive for the development of memory elements. There are totally three resonances in a NMR with the discussed tandem driving. The distance between the resonances on the frequency scale is much larger than the width of the individual resonances. Hence, the resonances are well localized in the frequency domain, and they can be used (excited) individually or collectively. Practically, such single NMR is equivalent to three NMRs with harmonic driving. The central frequencies of the two- and three-frequency resonances are easily controlled in a wide range by varying the LF. We have considered, as an example, a NMR made of a doubly-clamped beam with magnetomotive driving. However, due to the generality of the mathematical model used, the obtained results are applicable to other types of resonators and are not only limited to the nanosize scale.

C.5.3
12:30 Lunch break    

Symposium organizers
Andrea ILLIBERISolliance/TNO and Delft University of Technology

5656 AE, Eindhoven The Netherlands

andrea.illiberi@tno.nl
Christophe DETAVERNIERGhent University

Krijgslaan 281/S1, 9000 Gent, Belgium

christophe.detavernier@ugent.be
Davide BARRECAPadova University IENI-CNR c/o Department of Chemistry

Via Marzolo 1, I-35131 Padova, Italy

davide.barreca@cnr.it
Fred ROOZEBOOMEindhoven University of Technology

5600 MB, Eindhoven, The Netherlands

f.roozeboom@tue.nl
Marlies K. VAN BAELHasselt University and IMEC, Institute for Materials Research (imo-imomec)

Martelarenlaan 42, B-3500 Hasselt, Belgium

marlies.vanbael@uhaseselt.be
Thomas D. ANTHOPOULOSImperial College London

Department of Physics & the Centre for Plastic Electronics, London SW7 2AZ, United Kingdom

t.anthopoulos@imperial.ac.uk