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Nanomaterials, nanostructures and nano-devices


Nanomaterials - electronics & -photonics

Introduction and scope:

This symposium will cover:

(i) Growth of nanomaterials: From 0D - 3D networks.
(ii) Characterizations: Structure-property Relations, Modeling & Simulations.
(iii) Applications: (a) Plasmonics/ Nanophotonics (b) Nanoelectronics-Chemical/ Gas/ Biological/Stress Sensors (d) Piezotronics (d) Photovoltaics (e) Photocatalysis (f) Biomedical.

Nanoscale structures particularly from inorganic materials and carbon family are very important material candidates because of their size and shape dependent interesting physical and chemical properties suitable for various technological applications. The ongoing developments in the direction of 2D and 3D cellular materials have become further very relevant in terms of application aspects because, on one hand, they exhibit the necessary nanoscale features, and on the other hand, they exhibit less utilization complexities. Due to their sufficiently large size, they can be easily handled or integrated in desired manner in the devices or sensors. Due to interesting plasmonic properties, 0D, 1D, 2D nanostructures from noble metals (Au, Ag, Cu, etc.) have found immense applications in sensing, biomedical, waveguides and telecommunications, etc. Nanostructures from metal oxides have been very interesting (fundamental as well applied) materials due to interesting bandgap values (intermediate between metals and insulators) suitable for various advanced technological applications. When these metal oxides are combined with metals in form of hybrid nanomaterials, they become further very relevant in terms of understanding the properties and accordingly applications. The family of carbon nanostructures, i.e., fullerenes, carbon nanotubes, graphene, graphene oxide, etc., has shown very strong potential ranging from fundamental properties to advanced energy applications and hence has been the subject of great attention in the past decades and the recent developments in the direction 3D carbon networks have opened an entirely new dimensions in nanotechnology research. Research on 3D flexible ceramics from metal oxides interconnected networks, which is currently going on now-a-days, is very important because it can be very helpful in up scaling the nanotechnology related applications. However, the appropriate growth of different structures (0D, 1D, 2D and 3D) using simple methods, understanding their structure-properties relations, their applications in different directions, etc., are still very interesting aspects and it requires an interdisciplinary research platform which are equipped with: (i) fabrication groups for developing different nanostructures, (ii) computational scientists who can do simulations to understand the structure-property relations, and (iii) application groups who can accordingly utilize the nanostructures in different applications and this is actually the main aim of the present symposium.

Hot topics to be covered by the symposium:

  • Plasmonic Nanostructures & Nanocomposites: Synthesis & Characterizations, Computational Modeling, Sensing and Nanophotonics Applications.
  • Metal Oxides (0D to 3D) & Hybrids: Fabrication & Characterizations, Structure-Property Relations, Simulations Studies, Applications: Sensing, Biomedical, Energy Harvesting, Environmental, Porous Membranes, etc.
  • Carbon Nanostructures (Fullerenes to 3D Graphene): Fabrication & Characterizations, Structure-property relations, Theoretical studies, Applications: Nanoelectronics, Sensing, Supercapacitor, Batteries, Energy, etc.
  • 3D Porous Materials: Flexible Ceramics, Flexible Electronics, Biomedical Applications.       
  • Synchrotron Radiation Based Nanostructural Characterizations, Energetic Ions Beam Based Materials Synthesis & Modification.

List of invited speakers:

  • Oliver Schmidt, Germany
  • Jörg Hübner, Denmark
  • Jana Zaumseil, Germany
  • Martina Gerken, Germany
  • Ashutosh Tiwari, Sweden
  • Mady Elbahri, Finland
  • Mikhail Brik, Estonia
  • Ion Tiginyanu, Moldova
  • Sanjeev Srivastava, India
  • Junyi Zhai, China
  • Ha Dong Kim, South Korea
  • Cenk Aktas, Germany
  • Ravindra Pandey, USA
  • Ashutosh Tiwari, USA
  • Om Prakash Sinha, India
  • Santosh K C, USA


Symposium D papers will be published in Vacuum (Elsevier) Journal with Impact Factor ~ 1.55 (Web of Science).
For journal detail proceed, see
For submission go to:
During submission select special issue EMRS16D_ykm (will be active soon).

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Nanophotonics, Plasmonics & Sensing : Jost Adam
Authors : Christine Kallweit, Matthias Bremer, Torben Karrock, Prof. Dr. Martina Gerken*
Affiliations : Faculty of Engineering, Kiel University, Kaiserstr. 2, 24143 Kiel, Germany

Resume : Smart surfaces with switchable properties hold great promise for future integrated systems. Azobenzene molecules may be switched reversibly between the trans and cis isomer, which differ markedly in their molecular geometries and their electronic properties. We functionalize glass and polydimethylsiloxane (PDMS) surfaces employing a simple polydopamine-assisted process. Fluorinated azobenzene derivatives with a terminal amine group are linked to catechol binding sites, which are offered by polydopamine. Azobenzene concentrations of 2.5 mg/mL, 5.0 mg/mL and 10.0 mg/mL are tested. Much better performance is observed with first binding the azobenzene molecules to nanoparticles and subsequent application to the surface. A drop method and a spin coating process are compared for surface functionalization. Switching properties under light emitting diode (LED) and organic LED (OLED) illumination are presented, as these are suitable light sources for on-board switching in integrated systems.

Authors : Ning Zhou, Deren Yang and Dongsheng Li*
Affiliations : State Key Laboratory of Silicon Materials and School of Materials Science and Engineering, Zhejiang University

Resume : Strong coupling between semiconductor excitons and localized surface plasmons (LSPs) giving rise to hybridized plexciton states in which energy is coherently and reversibly exchanged between the components, promises applications in quantum control of light and quantum information processing. However, most of the studies focus on strong coupling with the manifestation of Rabi splitting and anticrossing behavior in view of extinction and reflection spectra, although the emission from the plexciton state modified by surface plasmons at the strong coupling regime has been intensively theoretically investigated. This raises the crucial question how to experimentally obtain emission at the strong coupling regime. In this paper, in photoluminescence (PL) spectra under nonresonant excitation at room temperature, we report on the direct observation of Rabi splitting and anticrossing-like behavior as an indication of strong coupling between excited states of CdSe/ZnS quantum dots (QDs) and LSPs modes of different metal nanostructures, including Ag nanoparticles, Au nanoparticles and silver nanoshells. We compared the different excitation characteristic of the hybridized plexciton states by these nanostructures. And we find that high pump energy and collective strong coupling of many QDs with the radiative dipole mode of the metallic NPs are essential to the realization of strong coupling.

Authors : Saskia Fiedler,* Cuong Ton-That, Matthew R. Phillips
Affiliations : School of Mathematical and Physical Sciences, University of Technology Sydney, Broadway, NSW 2007, Australia

Resume : The light extraction efficiency (LEE) of planar LED device structures is typically extremely low due to the abrupt change in refractive index at the device to air interface causing strong internal reflection. In this work, an anti-reflection coating consisting of a composite of ZnO nanorods (NRs) and Au nanoparticles (NPs) is investigated using optical and cathodoluminescence (CL) spectroscopy techniques to determine the utility of surface plasmon coupling and light waveguiding to improve LEE of LEDs. ZnO NRs with an average diameter of 40 nm and length of 700 nm have been grown hydrothermally at 90°C. A simple sputtering process was used to cover the NRs Au 1 nm thin film. Thermal annealing produced a continuous, uniformly distributed layer of 5 nm Au NPs which exhibited a broad plasmon absorption centred at 490 nm. Depth-resolved CL spectroscopy was performed at 80 K and 300K on as-grown bare as well as the Au thin film and Au NP coated ZnO NRs. The CL spectra of as-grown ZnO NRs at 80K exhibit a broad deep level (DL) emission band centred at 1.94 eV attributed to native point defects and a relatively sharp, more pronounced near band edge (NBE) peak at 3.36 eV. A 5 times increase of the NBE emission compared with the bare NRs is observed with the 5nm Au NPs and 1.5 times in the Au sputtered film. This enhancement of the LEE is attributed to strong coupling between ZnO excitons and Au surface plasmon polaritons.

Authors : Marco A. Squillaci,* Paolo Samorì
Affiliations : ISIS & icFRC, University of Strasbourg and CNRS, 8 Allée Gaspard Monge, 67000 Strasbourg, France.

Resume : Metal and, in particular, gold nanoparticle (Au NPs) have attracted great interest due to their unique physical and chemical properties: they can be easily synthetized in different media with a good control over size and distribution. Moreover Au NPs can be covalently functionalized with thiolated molecules to add new functionalities and to make stable organic/inorganic hybrids that can be used for a wide range of applications. Among them, one of the most promising one is the development of sensors specific for different analytes depending on the chosen thiolated ligand. In this work we report on a new scaffold based on 3D networks made by AuNPs, interconnected and cross-linked by tetra-ethyleneglycol dithiol (SH-TEG-SH) bridges as electrical resistive humidity sensors. The use of SH-TEG-SH gives great control over the distance between each nanoparticle ensuring the charge transport by tunnelling effect through the network and a good flexibility of the system that undergoes swelling upon absorption of very small amounts of water molecules from the atmosphere. Upon absorption of water, even a very small increase in the distance between the particles can dramatically decreases the tunnelling current through the network, making the device extremely sensitive over a wide range of condition: from ppm to 100% of relative humidity. Moreover these devices can be made on any kind of substrate and, being covalently attached to the measurement electrodes, can be washed and immersed in water without affecting the performances.

Authors : Atrayee Hazra,* Mallar Ray
Affiliations : Dr. M. N. D. School of Materials Science and Engineering Indian Institute Engineering Science and Technology, Shibpur Formerly known as Bengal Engineering and Science University, Shibpur Howrah, West Bengal-711103 India

Resume : Gold silver coupled nanostructure system presents immense possibilities for understanding plasmon-plasmon interaction. Although the origin of localized surface plasmon resonance (LSPR) in noble metal nanostructures and the dependence of LSPR on various factors have been widely investigated, the interaction of plasmons is still not clearly understood. In this work we present synthesis of Au@ Ag and Ag@ Au core@ shell nanostructures i.e. the materials of the core and the shell can be interchanged. For such interchangeable core@ shell noble metal nanostructures, we see that the plasmon-plasmon interaction is not only dependent on the size, shape, polarities etc but also on the position of a particular metal in the composite structure. Experimentally the LSPR interaction is studied by simple absorption spectroscopy and the structure is investigated by electron microscopy. A simple classical damped harmonic oscillator model is utilized to understand the plasmon-plasmon interaction in such systems. We show that this interaction can be accounted by a coupling parameter. Such core shell nanostructures with interchangeable core and shell materials offer huge potential for various applications.

Plasmonics for Photovoltaics & Advanced Applications : Jani Kotakoski
Authors : Prof. Dr. Mady Elbahri
Affiliations : Nanochemistry and Nanoengineering, School of Chemical Technology, Aalto University, Kemistintie 1, Aalto 00076, Finland

Resume : Although it is common to deposit or embed plasmonic dipoles in a transparent “neutral” matrix, blackbody host is another alternative of neutral hosting that has not been examined so far. Here a new concept of plasmonic metmaterials with almost perfect absorption of light within the whole visible spectrum, yet in colour fashion will be introduced. It is shown that this method and concept is applicable for different noble metals and the high absorption is polarization insensitive and angle invariant. Furthermore the fabrication technique is costeffective and compatible with current procedures in the MEMS industry.

Authors : Aleksandra Sierant,* Benedykt Jany, Dobros?awa Bartoszek-Bober, Jacek Fiutowski, Tomasz Kawalec, Jost Adam*
Affiliations : Marian Smoluchowski Institute of Physics, ?ojasiewicza 11, 30-348 Cracow, Poland; Marian Smoluchowski Institute of Physics, ?ojasiewicza 11, 30-348 Cracow, Poland; Marian Smoluchowski Institute of Physics, ?ojasiewicza 11, 30-348 Cracow, Poland; NanoSyd, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark; Marian Smoluchowski Institute of Physics, ?ojasiewicza 11, 30-348 Cracow, Poland; NanoSyd, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark;

Resume : Surface plasmon polaritons (SPPs) are collective electron oscillations, confined at metal-dielectric interfaces. Coupling incident photons to SPPs may lead to spectrally broad field enhancement and confinement below the diffraction limit [1]. This phenomenon facilitates various applications, including highly sensitive refractive index sensing [2], and plasmonic dipole mirrors for cold atoms [3]. Key to a successful application is a strong photon-to-SPP coupling. To this end, prism-based coupling is classically used, but this method contradicts compact device applications. An alternative realization is given by the use of a metallic diffraction grating, where the diffracted light couples to the SPP. Here, we propose metallic periodic transmission gratings, processed onto a glass substrate, with various periods and fill factors. The gratings are milled in a plain gold layer with a focused ion beam (FIB) microscope, using gallium and a neutralizing electron beam. We investigate the SPP coupling strength with respect to varying top layers and under collimated, oblique-angled excitation, with respect to the effect of finite gratings as opposed to perfect periodicity. We characterize the proposed plasmonic transmission gratings via near-field optical scanning microscopy (NSOM) and goniometric far field measurements. We support the evidence of our analyses with numerical calculations, carried out via rigorous coupled wave analysis (RCWA) and finite-difference in time-domain (FDTD) Simulations. [1] W. L. Barnes, A. Dereux, T. W. Ebbesen, Nature 424, 824?830 (2003) [2] X. D. Hoa, A. G. Kirk, M. Tabrizian, Biosensors and Bioelectronics, 23, 2, 151-160 (2007) [3] T. Kawalec, et al., Opt. Lett. 39, 2932 (2014)

Authors : Jacek Fiutowski,* Till Leißner, Oksana Kostiucenko, Elzbieta Sobolewska, Jost Adam and Horst-Günter Rubahn
Affiliations : NanoSyd, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark

Resume : Nanophotonics deals with the generation, modulation, guiding and detection of photons in a confined system at the nanoscale. Utilizing organic functional molecules as the building blocks of nanophotonic materials and components has great potential due to the multiple advantages, including the molecular design ability and tailorable properties. Our recent studies demonstrated the existence of an effective channel for energy transfer between organic materials and plasmonic structures. Our main experimental efforts are focused on hybrid organic-plasmonic platforms based on epitaxial grown organic nanofibers, deposited on flat metal surfaces or propitiously placed nearby suitable designed SP couplers. The principle of plasmons generation and guiding has been investigated by the leakage radiation spectroscopy and fluorescence-lifetime imaging microscopy (FLIM). Experimental studies have been complemented by numerical simulations for the same configurations. These findings will give possible advances in many applications and make organic nanoaggregates attractive for further optical device fabrication.

Authors : José V. Anguita,* James Clark, S. Ravi P. Silva
Affiliations : Advanced Technology Institute (ATI), University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.

Resume : There is a requirement to eliminate the use of bulky and curved refracting lensing components from the optical components used in today?s projection, imaging and sensing equipment. Replacing these with compact media is critical to enable optical system compactness. One means of achieving this miniaturization is by using a Veselago lens. However, this lens requires a material with a negative index of refraction. The production of these for broadband operation at visible frequencies has proven technically challenging. Here we introduce an alternative approach that enables the generation of a highly-collimated, wide-diameter beam using compact optical medium in flat-slab form, without the use of negative-index materials. We base our approach on light collimation using nanomaterials in nanoscale patterns designed to provide a highly anisotropic absorption coefficient. The nanostructures are able to strongly absorb light rays travelling along unwanted off-axis directions, whilst transmitting the desired (on-axis) rays. Whilst non-lensing, this technique can be used to circumvent the technical challenges of current negative-index metamaterials. In addition, we show this nanostructure can be embedded into a flexible transparent polymer matrix.

Authors : Vishal Mutreja,* Shweta Sareen, Satnam Singh and Bonamali Pal
Affiliations : Vishal Mutreja; Department of Chemistry, Maharishi Markandeshwar University, Mullana, Ambala-133207 Shweta Sareen;School of Chemistry & Biochemistry, Thapar University, Patiala-147004, Punjab, India Satnam Singh;School of Chemistry & Biochemistry, Thapar University, Patiala-147004, Punjab, India Bonamali Pal;School of Chemistry & Biochemistry, Thapar University, Patiala-147004, Punjab, India

Resume : Nanocomposites of SBA-15 and three coinage metals Au, Ag and Cu were synthesized by the sequential impregnation method, where mesoporous silica acted both as a host as well as a nanoreactor for uniform dispersion of implanted ternary nanoparticles. The prepared composites were characterized by DRS, powder XRD, TEM, EDX, elemental mapping, BET, FTIR, and XPS studies. TEM micrographs depicted the presence of highly dispersed small spherical nanoparticles (size ~5-7 nm) inside the sieves. EDX and elemental mapping studies confirmed the existence of Au, Ag and CuO nano species in the silica matrix. XPS studies established the presence of metallic Au and Ag while Cu was present in the form of CuO. Moreover, it was found that each particle corresponds to a separate entity rather than an alloy or core-shell structure within the mesoporous sieves. The catalytic activity of the synthesized composites was evaluated for the benzyl alcohol oxidation using H2O2 as the oxidant. Ternary composites showed exceptionally high catalytic activity for the selective oxidation of benzyl alcohol to benzaldehyde (87 %) with small amounts of benzyl benzoate, in comparison to bare SBA-15, and various other bimetallic combinations of coinage metals like Au-Ag, Au-Cu, and Ag-Cu respectively, ascribed to the small particle size, uniform dispersion and improved synergism between the different metal nanoparticles present in the siliceous matrix.

Semiconductor Nanostructures Optoelectronics and Solar Cells : Jost Adam
Authors : Rui Huang,* Zewen Lin, Zhenxu Lin, Yanqing Guo, Jie Song, Chao Song, Hongliang Li
Affiliations : School of Physics and Electronics Engineering, Hanshan Normal University

Resume : In the past decade, Si-based light sources compatible with the mainstream complementary metal-oxide semiconductor technology have attracted a great deal of interest owing to their potential application in monolithic Si optoelectronic integrated circuits[1-3]. To engineer Si into a more efficient light-emitting material, different approaches such as low-dimensional Si systems have been developed[3-5]. In our work, near-infrared (NIR) luminescent Si-rich oxynitride nanostructures were fabricated by very high frequency plasma enhanced chemical vapor deposition followed by thermal annealing. Increasing the annealing temperature up to 1100 °C result in the formation of Si nanocrystals (NCs) embedded in Si oxynitride matrix, which produces strong NIR emission. The analyses of the PLE spectra, the infrared absorption spectra and X-ray photoelectron spectra indicate that the photoexcited carriers for the enhanced NIR emission mainly originate in the quantum confined Si NCs, while their radiative recombination occurs in the surface states related to N-Si-O bonds. Interestingly, it is found that increasing the nitrogen content from 1% to 21% in the Si oxynitride matrix can effectively reduce the NIR luminescence lifetime from 50 to 2 microseconds and significantly enhance the NIR emission by more than an order of magnitude. The reduction of the NIR luminescence lifetime is attributed to the nitride passivation of Si NCs due to the Coulomb interactions. The experimental results indicate that the increase of O-Si-N surface states as well as the faster radiative recombination rates is responsible for the remarkable enhancement in NIR light emission. Acknowledgments This work was supported by National Natural Science Foundation of China (Nos. 61274140) and NSF of Guangdong Province (2015A030313871). Reference 1.L. Pavesi, L. Dal Negro, C. Mazzoleni, G. Franzò, and F. Priolo, Optical gain in silicon nanocrystals, Nature 408(6811), 440?444 (2000). 2.R. Huang, H. Dong, D. Wang, K. Chen, H. Ding, X. Wang, W. Li, J. Xu, and Z. Ma, Role of barrier layers in electroluminescence from SiN-based multilayer light-emitting devices, Appl. Phys. Lett. 92(18), 181106 (2008). 3.R. Huang, J. Song, X. Wang, Y. Q. Guo, C. Song, Z. H. Zheng, X. L. Wu, and P. K. Chu, Origin of strong white electroluminescence from dense Si nanodots embedded in silicon nitride, Opt. Lett. 37(4), 692-694 (2012). 4.X. Wang, R. Huang, C. Song, Y. Guo, and J. Song, Effect of barrier layers on electroluminescence from Si/SiOxNy multilayer structures, Appl. Phys. Lett. 102(8), 081114 (2013). 5.R. Huang, Z. Lin, Z. Lin, C. Song, Y. Guo, X. Wang, and J. Song, Suppression of hole overflow and enhancement of light emission efficiency in si quantum dots based silicon nitride light emitting diodes, IEEE J. Sel. Top. Quantum Electron. 20(4), 8200306 (2014).

Authors : Stanislav V. Zabotnov,* Fedor V. Kashaev, Dmitrii V. Shuleiko, Leonid A. Golovan, Pavel K. Kashkarov, Daria A. Loginova, Pavel D. Agrba, Ekaterina A. Sergeeva, Mikhail Yu. Kirillin
Affiliations : Lomonosov Moscow State University, Physics Department, 1/2 Leninskie Gory, Moscow, 119991 Russia; Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., Nizhny Novgorod, 603950 Russia; Institute of Applied Physics RAS, 46 Uljanov str., Nizhny Novgorod, 603950 Russia

Resume : Currently silicon nanostructures have high potential not only for novel micro- and nanoelectronic devices development, but for biomedical applications as well [1]. In our work, ensembles of silicon nanoparticles (2 ? 200 nm) fabricated through pulse laser ablation in water, and porous silicon nanocrystals (2 ? 50 nm) fabricated through electrochemical etching were studied as potential contrasting agents for optical coherence tomography (OCT). The silicon nanoparticle ensembles demonstrate effective light scattering for the both fabrication methods. The revealed scattering coefficient values of water suspensions formed via laser ablation method is presented in [2] for the visible and near-infrared ranges. The diffuse reflectance value of porous silicon layers reaches up to 50% in the 1000 ? 1100 nm range. The 0.3% agar gel was used as a model object mimicking biotissue in OCT. The laser-ablated nanoparticles or the mechanically grinded porous silicon were topically applied on the phantom surface yielding contrasting of maximum 14 dB and 30 dB respectively. A sequential combining of the electrochemical etching and laser ablation techniques for manufacturing of the silicon-based contrasting agents is considering also now. The work was financially supported by the Russian Foundation for Basic Research (project 15-32-20227). 1. R. Henstock, L.T. Canham, S.I. Anderson. Acta Biomaterialia 11, 17?26 (2015). 2. M.Yu. Kirillin, E.A. Sergeeva, P.D. Agrba, et al. Las. Phys. 25, 075604 (2015).

Authors : Malgorzata Wawrzyniak-Adamczewska,* Malgorzata Wierzbowska
Affiliations : Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland; Institute of Physics, Polish Academy of Sciences (PAS), Al. Lotnik\'ow 32/46, 02-668 Warszawa, Poland

Resume : Organic ferroelectric layers and molecular columns, arranged between the graphene sheets, are discussed for the solar cell application. The proposed layers possess many advantageous properties: 1) the cascade energy-levels alignment, 2) simultaneous donor and acceptor character depending on the charge-carrier direction, 3) the charge-transfer excitonic type, 4) the induced polarization of the electrodes, leading to a substantial work-function change of the anode and cathode - around $\pm$1.5 eV, respectively.\cite{RSC} The separate-path electron and hole transport is theoretically predicted for the layers, as well as for molecular columns. The carriers separation effect allows to deal with the charge recombination problem.\cite{JPhysC} The building molecules contain the mesogenic flat aromatic part and the terminal dipole groups which make the system ferroelectric.\cite{Sobol} The diffusion path of the electrons cuts through the aromatic rings, while holes hop between the dipole groups. The transmission function and the charge mobilities, especially for the holes, are very sensitive to the distance between the molecular rings, due to the overlap of the $\pi$-type orbitals. The influence of inelasctic effects on mobility function is also discussed. We verified that the separation of the diffusion paths is not destroyed by the application of the graphene leads. These features make the considered systems suitable for the efficient solar cells. \\ {\footnotesize This work has been supported by The National Science Centre of Poland: the Projects No.\\ 2013/11/B/ST3/04041 and DEC-2012/07/B/ST3/03412. Calculations have been performed in the Cyfronet Computer Centre using Prometheus computer which is a part of the PL-Grid Infrastructure.} \begin{thebibliography}{0} \bibitem{RSC} M. Wierzbowska, M. Wawrzyniak-Adamczewska, {\it Cascade donor--acceptor organic ferroelectric layers, between graphene sheets, for solar cell applications}, RSC Adv., 2016, {\bf 6}, 49988--49994. \bibitem{JPhysC} M. Wawrzyniak-Adamczewska, M. Wierzbowska, {\it Separate-Path Electron and Hole Transport Across $\pi$--Stacked Ferroelectrics for Photovoltaic Applications}, J. Phys. Chem. C, 2016, {\bf 120 (14)}, 7748--7756. \bibitem{Sobol} A. L. Sobolewski, {\it Organic photovoltaics without p--n junctions: a computational study of ferroelectric columnar molecular clusters}, Phys. Chem. Chem. Phys., 2015, {\bf 17}, 20580--8. \end{thebibliography}

Authors : Mahya Ganjian, Mohammadreza Kolahdouz*, Saeed Pourjafari, Matin Sadat Sanei Mousavi
Affiliations : ECE Department, School of Electrical and Computer Engineering University of Tehran, Tehran, Iran Email:

Resume : Recently, QD materials have been excited photovoltaic society due to their potential in optoelectronic applications. Quantum dots are nanoparticles with tunable band gaps from the visible to IR range. As a result of changing the size of these nanoparticles, different wavelengths of light can be absorbed or emitted. So these nanoparticles are one of the suitable choices to use as a photosensitizer in 3rd generation solar cells. This study reports fabrication and optimization of the QD sensitized cells on ZnO NRs which were grown by hydrothermal method. CdS and ZnS QDs were synthesized on the surface of ZnO NRs by successive ionic layer adsorption and reaction (SILAR) approach. We have investigated the effect of the counter electrode choice, size of the CdS QDs, and the concentration of components of polysulfide electrolyte on the cell efficiency. The optimum thickness of ZnS layer to have the best charge transfer was obtained. The cell with ZnO/CdS(C4)/ZnS(C3) as the photosensitizer, CuS as the counter electrode and Na2S 0.6 M, S 0.2 M and KCl 0.4 M in methanol/water (7:3) exhibited the best performance. The morphology of ZnO NRs was observed by field emission electron microscope. HRTEM was utilized to check the size of the CdS QDs. The crystal orientation of ZnO NRs was analyzed with X-Ray diffraction. UV-vis was employed to check the optical and electrical characteristics of the grown structures. Finally, J-V measurements were performed by Solar Simulator at (AM 1.5,100 mW/cm2) to extract the cell efficiency, Jsc, Voc and the fill factor.

Authors : Michael D. Weber,* Rubén D. Costa
Affiliations : Department of Chemistry & Pharmacy, University of Erlangen-Nuremberg, Egerlandstr.3, 91058 Erlangen, Germany

Resume : Currently, the main focus of solid-state lighting (SSL) technologies lies on replacing expensive and non abundant materials following the concept of Green Photonics. Here, organic light-emitting diodes (OLEDs) and light-emitting electrochemical cells (LECs) exhibit the potential to fulfill this concept. However, the OLED manufacturing process features a high cost and a lack of recycling protocols. Another bottleneck is the device architecture with several functional layers and air-unstable electrodes along with the need of encapsulation. To tackle these aspects, LECs have emerged as an interesting alternative due to the use of air-stable electrodes, as well as the simple device architecture that consists of only a single layer. Their fabrication protocol under ambient conditions is compatible with low-cost and solution-based processes. All of these features make this young technology very attractive for commercial applications. The best performing LECs consist of at least one active layer containing either a mixture of a light-emitting polymer, an ion conducting polymer and an inorganic salt (PLECs) or only one ionic transition-metal complex (iTMC) based on Ir(III) (Ir-iTMC-LECs).[1] Recently, a third generation of sustainable luminescent materials has been explored, namely small-molecules (SM-LECs) and iTMCs based on Cu(I) (Cu-iTMCs).[2] So far, only a few examples of yellow, green, and red devices have been demonstrated. Here, we present two of our most recent achievements towards environmentally friendly LECs. Firstly, we will show the first blue-emitting Cu-iTMC-LEC featuring a luminescence of 300 cd/m2 and x/y color coordinates of 0.23/0.28.[3] Secondly, the first white emitting SM-LEC based on a red-emitting TIPS-pentacene will be presented.[4] Here, we illustrate how to control the chromaticity of the device by means of a straightforward procedure, achieving either deep-red emission with x/y color coordinates of 0.69/0.31 and irradiance of 0.4 µW/cm2 or warm white devices with x/y color coordinates of 0.36/0.38 and luminances of ~ 10 cd/m2. [1] R. D. Costa, E. Ortí, H. J. Bolink, F. Monti, G. Accorsi, and N. Armaroli, Angew. Chem. Int. Ed., 2012, 51, 8178?211. [2] S. Tang, W.-Y. Tan, X.-H. Zhu, and L. Edman, Chem. Commun, 2013, 49, 4926?4928. [3] M. Elie, F. Sguerra, F. Di Meo, M. D. Weber, R. Marion, A. Grimault, J.-F. Lohier, J.-L. Renaud, R. D. Costa, M. Linares, M. Hamel, S. Gaillard, ACS Appl. Mater. & Interfaces, 2016 (in press). [4] M. D. Weber, M. Adam, P. R. R. Tykwinski, and R. D. Costa, Adv. Funct. Mater., 2015, 25, 5066-5074.

Authors : Thang Phan Nguyen, Quyet Van Le, and Soo Young Kim*
Affiliations : School of Chemical Engineering and Materials Science, Chung-Ang University 22, Heukseok-dong, Dongjak-gu, Seoul 156-756, Republic of Korea

Resume : Recently, two-dimensional transition metal dichalcogenides (TMDs) are attracted researchers. TMDs contains layer by layers structure with weak bonding Van der Waals which is similar with graphene layer bonding. Furthermore, bulk materials of TMDs have indirect bandgap but it change to direct bandgap in single layer. Here-in, we represent two-dimensional transition metal disulfides (TMDs) nanosheets, including MoS2, WS2, TaS2 and TiS2 by using sonication method. From bulk materials, TMDs were exfoliated into single and few layers with few hundred nanometer in size. MoS2 and WS2 nanosheets were continuously applied refluxing to reduce size into nanodots with few nanometer size. These nanosheets and quantum dots were applied to organic photovoltaic cell (OPV) and organic light-emitting diode (OLED). With UV/ozone treatment, TMDs nanosheets increase stability in air and the efficiency are comparable to traditional hole injection layer layer of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate). Exfoliated MoS2, WS2, TaS2, and TiS2 were applied to hydrogen evolution reaction (HER). The materials show low onset potentials of ∼100, 150, 175, and 135 mV, respectively, at a current density of -1 mA/cm2. MoS2 and TiS2 exhibited the best HER performance with Tafel slopes of 94.91 and 91 mV/decade. These results indicated that TMD nanosheets have potential applications as HER catalysts for the mass production of hydrogen. Key words: WS2, MoS2, TiS2, TaS2 2-D materials, nanosheets, OLED, HER, catalyst Acknowledgements This research was supported in part by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (No. 2014R1A2A1A11051098) and in part by the International Cooperative R&D program through Korea Institute for Advancement of Technology (KIAT) funded by the Ministry of Trade, Industry and Energy (MOTIE) of Korea.

Carbon Nanotubes and their Applications : Jan Kotakowski
Authors : Arko Graf, Yuriy Zakharko, Laura Tropf, Malte Gather, Prof. Dr. Jana Zaumseil*
Affiliations : Institute for Physical Chemistry, Universität Heidelberg, Germany; SUPA, School of Physics and Astronomy, University of St Andrews, United Kingdom

Resume : Single-walled carbon nanotubes (SWCNTs) are promising building blocks for future optoelectronic devices in the near-infrared. Owing to their unique optical properties, in particular their large oscillator strength, narrow emission linewidth and large exciton binding energy, we identify them as ideal candidates for strong light-matter coupling at room temperature. Here, we show strong coupling between the excitons of (6,5) SWCNTs and the photon modes of a metal-clad microcavity. We measure a Rabi splitting exceeding 110 meV, which is far in the strong coupling regime. We further demonstrate broadband tunability of light emission from dense (6,5) single-walled carbon nanotube thin films via efficient coupling to periodic arrays of gold nanodisks that support surface lattice resonances (SLRs). Emission from these hybrid films is spectrally narrow (20-40 meV) yet broadly tunable (~1000-1500 nm) and highly directional (divergence < 1.5°). In addition, SLR scattering renders the emission highly polarized, even though the SWNTs are randomly distributed (Zakharko et al. Nano Lett. 2016, 16, 3278?3284). In combination with their high charge carrier mobilities, SWCNTs open new paths towards practical exciton-polariton devices at telecommunication wavelengths.?

Authors : Jan Krajczewski,* Karol Kotaj, Andrzej Kudelski
Affiliations : Laboratory of Molecular Interactions, Department of Chemistry, University of Warsaw, Poland,

Resume : In 2010 Tian reported a new analytical method of chemical analysis of surfaces named SHINERS (shell isolated nanoparticle-enhanced Raman spectroscopy) [1]. In this approach the analyzed surface was covered with the layer of gold nanoparticles protected by a thin layer of silica or alumina, and then the Raman spectrum of the investigated sample was recorded. Gold nanoparticles act as electromagnetic resonators, significantly enhancing the electric field of the incident electromagnetic radiation, and hence leading to very large increase of the Raman signal from the surface on which nanoparticles have been spread. The protecting coating separates metal cores from direct contact with the probed material and keeps them from agglomerating. Therefore, metal nanoparticles covered with protecting layer might be used for broader range of systems, also for living cells. In this work we present photochemical method of synthesis of silver decahedral and a method of coating them by nanometric layer of silica. We investigated structural properties of obtained nanoparticles using Transmission Electron Microscope and their optical properties using UV-Vis spectrophotometer. Obtained nanoparticles have mainly decahedral shape and average edge length of 50 nm. The averaged thickness of the silica layer is ca. 3 nm. Synthesized decahedral nanoparticles exhibit maximum of absorption at 517 nm, whereas spherical nanoparticles at ca. 400 nm. The plasmonic peak for nanoparticles covered with silica layer is red shifted by several nm. We used obtained decahedral nanoparticles as SHINERS nanoresonators. As analyte we choose p-mercaptobenzoic acid and cell of yeasts (Saccharomyces boulardii). ACKNOWLEDGMENTS This project was financed from the funds of the National Science Centre allocated on the basis of the decision number DEC-2013/11/B/ST5/02224. 1 - Z. Tian et al, Nature 2010, 464, 392?395

Authors : Abasi Abudulimu, Florian Spaeth, Imge Namal, Tobias Hertel,b Larry Lüer*
Affiliations : Abasi Abudulimu; Larry Lüer; IMDEA Nanociencia, C/ Faraday 9, 28049 Cantoblanco, Madrid, Spain. Florian Spaeth; Imge Namal; Tobias Hertel; Institute of Physical and Theoretical Chemistry, Julius-Maximilian University Wurzburg.

Resume : Single-walled carbon nanotubes (SWNTs) show high aspect ratio, thermal and chemical stability and charge mobility, and therefore are promising materials to improve charge extraction in organic photovoltaic (OPV) devices. However, record efficiencies of OPV devices containing SWNTs remain far below SWNT free ones, which has been ascribed to a lack of knowledge and control of the nanostructure. Since typical charge extraction times in OPV devices are in the microsecond range, the interplay of the desired charged states with long-lived neutral states such as triplet excitons becomes important. Triplet excitons have recently been demonstrated on (6,5) SWNT with an optical yield close to 32 %. Hence, the role of triplet states in the overall photovoltaic process must be considered. Here, we present transient absorption (TA) spectroscopy of (6,5) and (7,5) rich SWNT networks on a femtosecond to microsecond time scale. By a global analysis, we show the presence of an excess photobleach in both samples which can neither be assigned to singlet excitons nor to charged states. We assign this excess photobleach to triplet excitons and show for the first time the occurrence of triplet exciton transfer from the (6,5) to the (7,5) chirality on a 100 ps time scale. By comparing samples of different SWNT density and varying the pump intensity, we discuss the most probable scenario for triplet exciton generation.

Authors : Simon G King,* Vlad Stolojan, S Ravi P Silva
Affiliations : Advanced Technology Institute, University of Surrey;Advanced Technology Institute, University of Surrey;Advanced Technology Institute, University of Surrey

Resume : To harness the excellent uniaxial mechanical and electrical properties of carbon nanotubes in macro-scale applications, the nanotubes need to be aligned and the tube-to-tube or tube-to-matrix connection needs to be mechanically and/or electrically appropriate. Often this means CNT need to be purified and functionalised a priori, which leads to the CNTs requiring an alignment process. Electrospinning offers and ideal solution, as the thin polymer spun fibres confine and align CNTs along the fibre axis. We show a scalable electrospinning method of making large area paper (greater than A4-paper size) and metre-long cables of aligned CNTs using a water soluble polymer (poly-ethylene oxide). The polymer-CNT composite shows an increase of tensile strength and ductility by a factor of 3 and the Young?s modulus by a factor of 4. The aligned CNT wires showed an increase in PEO composite conductivity by two orders of magnitude. Removal of the polymer matrix results in CNT wires with conductivities of 140 S/m (for semiconducting CNTs).

Authors : V. Kaidas,* A. Vahl, S. Nöhren, F. Schütt, J. Carstensen, S. Kaps, F. Faupel, R. Adelung
Affiliations : Institute for Materials Science, Kiel University

Resume : Because of their huge technological relevance, memristive devices have been under significant discussion since 70?s [1] and different fabrication strategies have been adopted for their adequate realizations. In the early stages of the fabrication, memristors were mainly based on metal oxides and the observed memristive response was either the incorporation of oxygen vacancies or other ions (e.g. Ag ions) and their field induced drift inside of the matrix. A general overview about metal oxides based memristive is introduced in [1]. In this context, polymers [2] and biomaterials [3] are also being investigated as matrix materials in regard to their memristic effects. Very recently, carbon nanotubes (CNTs) have been found to exhibit interesting memristive effect which is main focus here. Our approach is based on the usage of CNTs and the formation of defined conducting networks between inert electrodes. As a first step, we brought carbons with different hybridization states into contact with semiconducting high aspect ratio materials in the micrometer regime and were able to successfully measure memristic characteristics [4]. By adding clusters into the network, it is now possible to introduce memristic effect which is mainly induced by the movement of the clusters. Our long term goal is to fabricate structures even with a higher range of interconnection with the outlook to obtain 3D memristive structures using this approach. Refs: [1] J. G. Simmons et al., , Proceedings of the Royal Society A 301 (1967) 1464. [2] V. Erokhin, et al., Nano Communication Networks 1 (2010) 108-117. [3] Y.-C. Chen, et al., Scientific Reports 5 (2015) 10022. [4] S. Nöhren et al., 2016, (manuscript under preparation).

Poster Session 1 : Jani Kotakoski, Jost Adam, Yogendra Mishra, Arul Murugan
Authors : Nanowires are an important class of one-dimensional (1D) nanomaterials that have been attracting a great deal of interest recently. Porous Silicon nanowires (PSiNWs) are one of the most important 1D semiconductors prepared by metal assisted chemical etching. In this paper we present the fabrication of PSiNWs doped with fluorescein-conjugated silane coupling agent (FiTC-APS) by immersion method. These nanostructures are characterized by TEM after fabrication. The PSiNWs doped FiTC-APS for different immersion time, are characterized by photoluminescence showing energy transfer from FiTC nanoparticles (521 nm) to PSiNWs (680 nm). The immersion time of 60 min present high-energy transfer compared to 10 and 80 min. The Raman measurements show a shift of the phonon peak towards lower wave number due to the porous structure and to change of porosity after immersion.
Affiliations : Adel Najar (1), Hakim Mehenni (2) Department of Physics, UAE University Al-Ain, P.O.Box 15551 United Arab Emirates

Resume : Nanowires are an important class of one-dimensional (1D) materials that have been attracting a great deal of interest recently. Porous Silicon nanowires (PSiNWs) are one of the most important 1D semiconductors prepared by metal assisted chemical etching. In this paper we present the fabrication of PSiNWs doped with fluorescein-conjugated silane coupling agent (FiTC-APS) by immersion method. These nanostructures are characterized by TEM after fabrication. The PSiNWs doped FiTC-APS for different immersion time, are characterized by photoluminescence showing energy transfer from FiTC nanoparticles (521 nm) to PSiNWs (680 nm). The immersion time of 60 min present high-energy transfer compared to 10 and 80 min. The Raman measurements show a shift of the phonon peak towards lower wave number due to the porous structure and to change of porosity after immersion.

Authors : A. Duzynska, M. Swiniarski, A. Wroblewska, A. Lapinska, K. Zeranska, J. Judek, M. Zdrojek
Affiliations : Faculty of Physics, Warsaw University of Technology, Koszykowa 75, 00-662 Warsaw, Poland

Resume : We report a temperature-dependent (70-450 K) Raman study of single-walled carbon nanotube (CNT) thin films as a function of their thickness and the conductivity type of the nanotubes used to fabricate these films. The CNT films Raman G mode positions and widths exhibit two apparent regimes, a nonlinear temperature dependence at low temperatures (<270 K), which is explained by the phenomenon of optical phonon decay, and a linear temperature dependence above 270 K. The first-order temperature coefficient, determined for the linear regime, depends on the film thickness and type of CNTs, changed up to 20%. In addition, we observed another factor causing phonon shifts that is not related to the temperature but strongly depend on the film thickness and conductivity type of the CNTs. Finally, we ascertained the local temperature changes of the film samples upon laser heating as a function of the global temperature, demonstrating significant differences in the heating process, suggesting that heat evacuation efficiency depends type of the film, its thickness and global temperature. These results contribute to the understanding of the thermal properties and heat dissipation in CNT films, which are crucial for use in a variety of future applications.

Authors : Na Kyoung Youn,[a] SeJin Ahn,[a] Ara Cho,[a] Jihye Gwak,[a] Kyunghoon Yoon,[a] Keeshik Shin,[a] Seung Kyu Ahn,[a] Jun Sik Cho,[a] Joo Hyung Park,[a] Jin Soo Yoo,[a] Kihwan Kim,[a] Jae Ho Yun,[a] and Young-Joo Eo *[a]
Affiliations : [a] Photovoltaic Laboratory, Korea Institute of Energy Research(KIER),Daejeon, Korea

Resume : Tin mono-sulfide (SnS) thin film has been investigated as a photovoltaic absorber material due to not only a high optical absorption coefficient but also non-toxicity and earth abundance. However, the highest photovoltaic conversion efficiency is as low as 4.4%. One of the reasons for the low efficiency is considered to be the poor quality of the SnS layer, such as the formation of secondary phases and a high grain boundary density. Thus, many research groups have dedicated their own effort to obtaining a high quality of SnS thin film. Nano-particle based approach can be one of the suitable fabrication methods of SnS thin films because the thin film can be prepared by a simple coating process using the nano-particle based ink, and the subsequent thermal annealing. The thermal annealing can transform the nano-particle precursors into the thin film and promote the grain growth. Moreover, it can affect the micro-crystalline structure of the thin film. Thus, we can control the physical properties of the SnS thin films by the modification of the thermal annealing condition. In this study, we focused on the effect of the thermal annealing condition on the properties of the SnS thin films. We have found that the crystallinity and band gap (Eg) of thin film are highly dependent on the thermal annealing temperature. The partial pressure of hydrogen sulfide (H2S) gas during the thermal annealing affects the valence of Sn atom and the composition of the thin film. Finally, we demonstrate a SnS thin film solar cell and characterize its photovoltaic performance.

Authors : S. Kratro Yu. Pogrebnyak
Affiliations : Department Electrophysics, Faculty of Radiophysics,Electronics and Computer Systems, Taras Shevchenko National University of Kyiv

Resume : The concept to these building blocks optical activity in surrounding is based on developed model for a photoresponse of complex on carbon nanotube, which has bond with modified by organic molecule ends and/or walls CNT. Such complex for using carbon nanosystems organization is a favorable tools for designing and synthesis of new hybrid carbon nanosystems as templates for biomolecules attaching and their biocompatibility and photoactivity. Functionalized carbon nanotubes (CNTs), having multifunctional application both as separated and as building blocks in cluster-assembled nanosystems and the method to functionalize CNTs with complexes, which are linked the СNTs by covalent bonds with possible bonding biomolecules, with novel functionalization of CNTs by aminoderevatives, that support formation of complex on carbon nanotube as building blocks.

Authors : Nuttawut Kongsuwan, Angela Demetriadou, Andreas Pusch, Ortwin Hess
Affiliations : Imperial College London

Resume : Quantum emitters placed in a cavity can coherently exchange energy with light in cavity modes. When the coherence time of the coupling is longer than the period of energy oscillation, the system reaches the strong coupling regime and shows characteristic Rabi splitting in its far-field spectrum. The phenomenon was previously thought to only occur at cryogenic temperature since high noise levels disrupt the coherence coupling. However, recent experiments have shown that strong coupling can be achieved at room temperature by reducing the mode volume to below 10 cubic nanometers using a plasmonic nanocavity. At room temperature, noise is prevalent, and it is essential to understand its effect on the strong coupling. Here, we treat the system semi-classically, using the Maxwell-Bloch Langevin approach, and correctly predicts the disappearance of Rabi splitting at high noise levels. We show the effect of noise on the spatial coherence between quantum emitters in the cavity and the ability of super-radiance emission.

Authors : A. Serrano, A. Arana, A. Galdámez, Romero-Ibarra Josue, A. Dutt, B.M. Monroy, G. Santana.
Affiliations : Instituto de Investigaciones en Materiales-Universidad Nacional Autónoma de México

Resume : Zinc oxide (ZnO) nanowires (NWs) were grown on Au coated aluminum-doped zinc oxide (AZO) thin films via vapor-liquid-solid (VLS) technique. AZO seed layers were deposited using the ultrasonic spray pyrolysis (USP) and magnetron sputtering. The effects of the seed layer on structural, morphological and optical properties of the NWs were analyzed by X-ray diffraction (XRD), scanning electronic microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques to characterize the structural and morphological characteristics of the ZnO nanowires. In addition, optical properties were also studied using photoluminescence (PL) spectroscopy. Results showed that structural and morphological properties of the grown NWs have a strong dependence on the seed layer. Nanowires with the orientation (101) show the growth in multi directions (zig-zag manner), whereas, with (002) orientation they show columnar growth. The same has been confirmed with the SEM images, which show that (002) NWs are better vertical aligned than (101) NWs. PL spectra show that irrespective of the preferential orientation, NWs showed a strong green emission when excited with He-Cd laser at room temperature. This could be due to structural defects induced during the VLS growth process, such as zinc or oxygen vacancies.

Authors : T. C. Cheng, T. H. Fang, W. S. Lin, and C. K Yang
Affiliations : Department of Mechanical Engineering, National Kaohsiung University of Applied Science, Kaohsiung, Taiwan

Resume : The effect of thiolated process and various mixture fluxes on the carbon nanotubes (CNTs) synthesis which were grown on the flexible carbon cloth using ethylene (C2H4) as the carbon source and nickel (Ni) as the catalyst by thermal CVD and microwave plasma chemical vapor deposition (MPCVD) were investigated in this paper. Our experiment results indicated that the average diameter and density of multi-wall carbon nanotubes (MWCNTs) will decrease with increasing N2 flux because nickel catalyst is easily passivated by carbonaceous particles with increasing N2 flux and nickel nitride was formed with increasing N2 flux so that the CNTs grow selectively on nickel portion instead of whole nickel. Besides, the effect of H2 gas for MWCNTs growth was explored. The experimental results showed that increasing the hydrogen concentration will enhances the catalyst activity to accelerate the formation of CNTs and will be able to reduce catalyst particle size so that the density of MWCNT will increase and the diameter of MWCNT will decrease. Furthermore, the higher N2 and H2 concentration will improve the quality of MWCNTs so it also increases the field emission properties of MWCNTs. Moreover, in order to improve the field emission properties of MWCNTs on flexible carbon cloth, the microwave plasma chemical vapor deposition (MPCVD) and a simple and effective two-steps chemical surface modification technique was also used to produce the well-aligned & open-ended thiolated MWCNTs. First, MWCNTs were modified by HNO3 to open the end of MWCNTs and this effect of the circular sharp edge of open-ended MWCNTs could result in higher field amplification at the emission area. Second, the thiolation of MWCNTs was introduced by a method based on the pre-formation of carboxylic bonds of MWCNTs by reacting with 2-mercaptoethanol (C2H6OS) in a dehydration reaction in order to decrease the work function of MWCNTs. Our fabricated thiolated MWCNTs reveal a very low threshold field value of 1.25 Vμm−1 and a rather high field enhancement factor of 1.93×104. The improved field emission properties of the thiolated MWCNTs were attributed to the combined effects of geometric enhancement of open ended MWCNTs and a lower electron affinity after thiolation, which have thus offered a useful solution with a large potential to fabricate low-threshold and high-efficiency field emitters for practical applications in flexible vacuum microelectronics.

Authors : Yong Tae Kim,* Seong-Il Kim, F. Gamiz
Affiliations : Semiconductor Materials & Devices Lab, Korea Institute of Science and Technology, Seoul 136-791, Korea; Departamento de Electronica y Tecnolog?a de los Computadores, Universidad de Granada, Avda. Fuentenueva s/n, 18071 Granada, Spain

Resume : Among graphite family, graphene oxide (GO) have many unique properties such as controllable band gap and high transmittance which are very essential for optical devices. In this work, we will present a simple, cost effective and precisely controllable methods to fabricate high-quality GO films as a hole injection layer (HIL) for high efficiency polymer light-emitting diodes (PLEDs. The deposition and reduction of GO films are electrical methods; hence the thickness and the degree of reduction for GO films can be easily manipulated by controlling electrical parameters and time. The performance of PLEDs with RGO film as HIL is measured and compared with GO and (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) (AI4083), and shows better results for luminance and current density. It is successfully demonstrated the EPD method and the electrical reduction to fabricate the RGO thin film alongwith their implementation for making high efficiency PLEDs. Since each layer of PLEDs is the non-alkali or non-alkaline earth metals, it facilitates us to fabricate PLEDs in the ambient environment. The thickness of the GO films could be controlled from 80 to 350 A with the EPD system. These deposited GO films were reduced by the electrical method. The GO films with various thicknesses and the RGO films with a different reduction degree were prepared to optimize the film for HIL layer. It has been observed that GO with 80 A thickness followed by 10 s reduction is the best candidate as HIL of PLEDs. The optimum condition could be confirmed by Raman spectroscopy, XPS, UPS and UV?Vis spectroscopy. Finally, we fabricated high efficiency PLEDs using RGO as HIL and compared the performance of the device with AI4083 HIL device. The maximum luminance was 12830 (RGO HIL) and 3,958 cd/m2 (AI4083 HIL). The EPD process and the electrical reduction method are expected to be useful as an industrial approach in fabrication of high efficiency PLEDs.

Authors : M. Norek,* W. Zaleszczyk, G. Łuka, M. Chojnacki
Affiliations : Military University of Technology, Kaliskiego St. 2, 00-908 Warsaw, Poland; Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, 02-668 Warsaw, Poland

Resume : In recent years, zinc oxide (ZnO), with a wide direct band gap (3.37 eV) and a large exciton binding energy (60 meV), has been considered as a promising candidate for efficient ultraviolet (UV) light-emitting devices (LEDs) and low threshold UV lasers [1]. For photonic applications of ZnO it is of outmost importance to obtain highly efficient UV emission from the near band edge (NBE). In nanostructures, ZnO-based device performance is determined essentially by the surface and near-surface properties because of the large surface-to-volume. The surface or sub-surface defect states can have a detrimental effect on luminescence or electrical properties of ZnO nanostructures, which limits their optoelectronic applications. Therefore, extensive research has been made to modify the surface of ZnO nanostructures by depositing a shell layer of various materials on the top of ZnO nanostructures forming a core/shell structure to improve the optical and electronic performances of the ZnO core materials [2]. In this work, the enhancement of NBE emission from regular, self-aligned and equal-spaced ZnO nanotubes upon deposition of thin Al2O3 layer was observed. The luminescence spectra were acquired at room temperature. The ZnO nanotubes of various wall thickness were prepared by anodic alumina template assisted synthesis and ALD technique, and the Al2O3 layer was deposited by ALD technique. [1] A. Janotti, C. G. van de Walle, Fundamentals of zinc oxide as a semiconductor, Rep. Prog. Phys. 72 (2009) 126501 (29pp). [2] J.-P. Richters, T. Voss, D. S. Kim, R. Scholz, M. Zacharias, Enhanced surface-excitons emission in ZnO/Al2O3 core-shell nanowires, Nanotechnology 19 (2008) 305202 (4pp).

Authors : Vanessa P. Scagion*, Luiza A. Mercante, Juliano E. Oliveira, Luiz H. C. Mattoso, Marcos D. Ferreira, Daniel S. Correa*
Affiliations : National Laboratory for Nanotechnology in Agribusiness (LNNA), Embrapa Instrumentation, 13560-970, São Carlos, SP, Brazil;Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), 13565-905, São Carlos, SP, Brazil; Engineering Department, Federal University of Lavras (UFLA), 37200-000, Lavras, MG, Brazil.

Resume : Chemical sensors based on eletronic tongues have shown to be a useful tool for food industry, aiming at evaluating food quality and contamination. Specifically, milk is considered to be a fundamental item for human dietary, especially for children, owing its nutritious components. However, analytical methods capable of evaluating the quality of milk are still on demand, once contamination by adulterants, such as antibiotics, can greatly alter its physical-chemical parameters, quality and taste, making the milk fully inadequate for human consumption. This work reports on the development of an electronic tongue (e-tongue) sensor for evaluating the UHT-type milk regarding the presence of the antibiotic tetracycline. The chemical sensor was composed by an array of sensing units comprising gold interdigitated electrodes, which were modified with Polyamide 6 (PA6)/polianyline electrospun nanofibers. The electronic tongue measurements were carried out using an impedance analyzer to collect electrical resistance of milk samples at 1 KHz. As chemometric tool we employed the Principal Component Analysis (PCA) technique to verify the efficiency of the new nanostructured platform for evaluating the milk samples regarding antibiotic contamination. The results demonstrated that the electronic tongue system is a potential methodology for the differentiation and classification of milk samples regarding the presence of the antibiotic tetracycline down to a few ppb.

Authors : Hyun jin Cho, Yong hee Lee, Won seok Choi, Duk young Jeon*
Affiliations : Korea Advanced Institute of Science and Technology(KAIST)

Resume : Quantum dots have unique optical properties from quantum confinement effect. There are many studies to apply them to display and lighting as a luminescence material. From previous study, luminescence from quantum rods which are one-dimensional structure of quantum dot has larger stokes shift, polarization property and can be quenched under external electric field compared to quantum dot. Especially, quantum rods can be used display materials because their charge separation property under external electric field is able to control luminescence. In this study, we synthesized CdZnS/ZnS core/shell rod-in-rod structure to achieve high quality blue emission. But rod-in-rod structure of CdZnS/ZnS core/shell quantum rod is unstable because ZnS shell is unstable on surface of CdZnS core for its anisotropic crystal structure. For practical application such as display materials and LED, stable luminescence of quantum rods is essential. This work deals with stability issues of blue emitting CdZnS/ZnS quantum rod structure and shows effort to enhance stability of CdZnS/ZnS quantum rod synthesized by using different shell precursor. So far, stability of CdZnS/ZnS quantum rods has been improved from 3 weeks to 2 months.

Authors : Su Yong Lee, Hyon Chol Kang*
Affiliations : Pohang Accelerator Laboratory, POSTECH, Pohang 790-834, Republic of Korea; Department of Materials Science and Engineering, Chosun University, Gwangju 501-759, Republic of Korea

Resume : The rutile phase of tin oxide (SnO2) has attracted significant attention owing to its outstanding properties such its wide bandgap (3.6 eV), optical transparency, high electrical conductivity, and gas sensitivity. Recently, SnO2 nanowires (NWs) with a large surface-to-volume ratio were easily fabricated and their potential for use in various electronic devices such as sensors, waveguides[6], and anode materials for lithium-ion batteries was thoroughly investigated. Several techniques, including hydrothermal methods, chemical vapor deposition, and vapor transport methods, have been proposed for the efficient synthesis of SnO2 NWs. Vapor transport methods, which require relatively simple designs, are the most viable of all these methods and are capable of producing high-aspect-ratio NWs. Although individual SnO2 NWs synthesized by vapor transport methods have distinct characteristics, they are typically characterized according to their growth morphology; i.e., they are classified as either NW bundles or wool-like NW mat. These classifications allow determination of the average physical properties. Only a few studies have reported the optical and electronic properties, such as improved gas sensing, and strong photo conducting response, of a single NW. In general, the microstructure of individual NWs can only be determined using transmission electron microscopy (TEM). In this paper, ultra-long (lengths >400 microns) SnO2 NWs were prepared using a vapor transport method. We examined individual SnO2 NWs by performing single-crystal X-ray diffraction (XRD) measurements; highly brilliant synchrotron X-rays are an excellent tool for investigating the structural properties of an isolated SnO2 NW. The XRD results revealed the single-crystalline nature of tetragonal-rutile-phase SnO2 NWs with mosaic distributions of 0.02 degree and 0.026 degree in the (101) and (110) planes, respectively. This single-crystalline nature was also confirmed using high?resolution TEM and micro-Raman spectroscopy measurements.

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Graphene based Advanced Nanomaterials : Jost Adam
Authors : Prof. Dr. Oliver G. Schmidt
Affiliations : Institute for Integrative Nanosciences, IFW Dresden, Germany and Material Systems for Nanoelectronics, Technical University Chemnitz, Germany

Resume : Nanomembranes are thin, flexible, transferable and can be shaped into 3D microtubular NEMS architectures. This makes them attractive for a broad range of applications and scientific research fields ranging from novel hybrid heterostructure devices to ultra-compact 3D systems both on and off the chip. If nanomembranes are differentially strained they deform themselves and roll-up into microtubular NEMS structures upon release from their mother substrate. Rolled-up nanomembranes can be exploited to rigorously compact electronic circuitry and energy storage units. They can also serve as ideal platform to study novel photonic and plasmonic phenomena. As rolled-up microtubes can be easily tuned into the size range of single cells, they are perfectly suited to study single cell behaviour in 2D confined systems and establish exciting environmental and biomedical applications such as biomimetic regenerative cuff implants or ultra-sensitive yet fully integrative lab-in-a-tube systems. If magnetic tubes or helices are combined with spermatozoa, such hybrid micro-biorobotic motors offer new perspectives towards paradigm shifting reproduction technologies.

Authors : Muhammad Arslan Shehzad,* Yongho Seo
Affiliations : Graphene Research Institute, Sejong University, Seoul 143-747, Republic of Korea; Faculty of Nanotechnology & Advanced Materials Engineering and Graphene Research Institute, Sejong University, Seoul 143-747, Republic of Korea

Resume : Although Chemical vapor deposition (CVD) is a good technique to synthesize large area 2D materials i.e. Graphene, MoS2 but boundaries between the grains, defects and grain size of these materials have great influence on the electronic and mechanical properties.[1] Usually these 2D synthesized materials are polycrystalline where scattering of charge carriers at grain boundaries can lead to degradation of its performance, compared to exfoliated single-crystal graphene or other TMDs.[2] The electrical properties of grain boundaries have so far been addressed indirectly without direct knowledge of their locations. Previously, we present a technique to measure the electrical behavior of individual grain boundaries imaged with the help of aligned liquid crystal.[3,4] Unexpectedly, the electrical conductance was degraded by three orders of magnitude for grain boundaries with the least on/off ratio. Here we studied the effect of UV exposure on aligned LC on graphene and observed p-type doping in the electrical properties. Interestingly on removal of LC, the doping effect can be removed as well and Dirac point could shift to its original state. We believe that LC alignment approach is versatile to alter the electrical properties of graphene and other TMDs based devices. Our study suggests a useful technique to fabricate devices on a single crystal area, using optimized growth conditions and device geometry. References: 1. Yazyev, O. V.; Louie, S. G. Nature Materials 2010, 9, (10), 806-809. 2. Huang, P. Y.; Ruiz-Vargas, C. S.; van der Zande, A. M.; Whitney, W. S.; Levendorf, M. P.; Kevek, J. W.; Garg, S.; Alden, J. S.; Hustedt, C. J.; Zhu, Y.; Park, J.; McEuen, P. L.; Muller, D. A. Nature 2011, 469, (7330), 389-+. 3. Shehzad, M. A.; Hussain, S.; Khan, M. F.; Eom, J.; Jung, J.; Seo, Y. Nano Research 2016, 9, (2), 380-391. 4. Shehzad, M. A.; Tien, D. H.; Iqbal, M. W.; Eom, J.; Park, J. H.; Hwang, C.; Seo, Y. Scientific Reports 2015, 5.

Authors : B. Dlubak,* M. Piquemal-Banci, R. Galceran, M.-B. Martin, C. Deranlot, R. Mattana, H. Jaffre?s, M. Sprinkle, C. Berger, W. de Heer, S. Xavier, B. Servet, A. Anane1, F. Petroff, A. Fert, P. Seneor
Affiliations : Unite? Mixte de Physique CNRS/Thales, 91767 Palaiseau, France and Universite? Paris-Sud, Orsay, France; GeorgiaTech, Atlanta, USA/Institut Ne?el, Grenoble, France; Thales Research and Technology, 1 av. A. Fresnel, 91767 Palaiseau.

Resume : Spintronics is a paradigm focusing on spin as the information vector. Ranging from quantum information to zero-power non-volatile magnetism, the spin information can be also translated from electronics to optics. Several spintronics devices (logic gates, spin FET, etc) are based on spin transport in a lateral channel between spin polarized contacts. We want to discuss, with experiments in support, the potential of graphene for the transport of spin currents over long distances in such types of devices. We will present magneto-transport experiments on epitaxial graphene multilayers on SiC [1]. The measured spin signals are in the mega-ohms range, and the analysis of the results in the framework of drift/diffusion equations leads to large spin diffusion length in graphene in the 100 microns range. The high spin transport efficiency of graphene can also be acknowledged up to 75% in our devices. These results will be compared to previous studies on carbon nanotubes and to our on-going study on large scale CVD grown graphene making use of h-BN tunnel barriers [2]. Our latest results of spin precession in graphene channels obtained at room temperature will be also discussed. A unified picture of spin transport in nanotubes and graphene will be presented [3]. [1] B. Dlubak et al. Nature Physics 8, 557 (2012). [2] M. Piquemal-Banci et al. Applied Physics Letters 108, 102404 (2016) [3] P. Seneor et al. MRS Bulletin 37, 1245 (2012).

Authors : Jani Kotakoski
Affiliations : Department of Physics, University of Vienna, Austria

Resume : Graphene, a one-atom-thick layer of carbon atoms, is a great material for studying the atomic structure of defects, their dynamics, and the correlation between the exact disorder structure and macroscopic properties. From the technological point of view, purposefully created defects can be used to control many of the properties of this material, which can lead to new applications in a variety of different fields. However, to do this in a controlled manner, very good control over the created defects is needed. One way to achieve this is to use energetic particles to introduce defects and to study in detail the resulting atomic structure. While this has been attempted to some extend, most of the structural analysis has relied on indirect spectroscopic data. In this presentation, I will present an enhanced theoretical model to describe electron beam knock-on damage in graphene with a high enough predictive power to determine isotope ratios from experimental graphene samples, describe large scale structural modification of graphene using electron and ion irradiation, as well as present results on implantation of foreign atoms into the graphene lattice using low-energy ions. Finally, the expected and observed changes that these structural manipulations have on the electronic properties of graphene will be discussed.

Authors : Tobias Cramer,* Adrica Kyndiah, Cristiano Albonetti, Mauro Murgia, Alexander Kloes, Beatrice Fraboni, Fabio Biscarini
Affiliations : Department of Physics and Astronomy, Universtiy of Bologna, Viale Berti Pichat 6/2, 40127 Bologna, Italy; Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), Via P. Gobetti 101, 40129 Bologna, Italy; Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), Via P. Gobetti 101, 40129 Bologna, Italy; Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), Via P. Gobetti 101, 40129 Bologna, Italy; Competence Center Nanotechnology and Photonics, Technische Hochschule Mittelhessen, 35390 Gießen, Germany; Department of Physics and Astronomy, Universtiy of Bologna, Viale Berti Pichat 6/2, 40127 Bologna, Italy; Life Science Dept., Università di Modena e Reggio Emilia, Via Campi 183, 41125 Modena, Italy

Resume : Understanding of interface effects in organic thin film transistors (OTFT) is key to realize high performance organic flexible electronics and organic sensor applications. OTFT exploit field effect to accumulate charge carriers into an almost 2D confined layer adjacent to the interface with the gate dielectric. Charge carrier density and transport in this channel depend not only on intrinsic semiconductor properties but can be largely tuned by interactions stretching across the semiconductors interfaces. Here we investigate interface effects in thin films containing pentacene and C60 as model compounds for organic electronics devices. Films of pure semiconductor and heterojunctions are grown by vacuum sublimation and their electrical properties are studied in-situ starting from the submonolayer regime. Displacement current measurements and temperature dependent transfer measurements are employed to quantify carrier density, mobility and trap levels as a function of layer thickness and morphology. Our findings provide quantitative descriptions for (i) charge density increase in submonolayer films [1]; (ii) charge transfer across the interface in heterojunctions [2] and (iii) band broadening due to interfacial disorder; [1] T. Cramer, A. Kyndiah, A. Kloes, M. Murgia, B. Fraboni, and F. Biscarini, Phys. Rev. B, vol. 91, no. 20, pp. 1?7, 2015. [2] A. Kyndiah, T. Cramer, C. Albonetti, F. Liscio, S. Chiodini, M. Murgia, and F. Biscarini, Adv. Electron. Mater., vol. 1, no. 11, p. 1400036, 2015.

Fabrication of Advanced 2D Nanomaterials : Yogendra Mishra
Authors : Prof. Dr. Ion Tiginyanu
Affiliations : Institute of Electronic Engineering and Nanotechnologies, Academy of Sciences of Moldova, Chisinau 2028, Moldova; National Center for Materials Study and Testing, Technical University of Moldova, Chisinau 2004, Moldova

Resume : Increasing attention is paid nowadays to the elaboration of cost-effective technologies of material nanostructuring for nanoelectronic and photonic applications. In this paper, we report on a novel approach, called Surface Charge Lithography (SCL), allowing direct writing of gallium nitride micro- and nanostructures. Note that GaN is presently the second most important semiconductor after Si. The proposed technological route comprises low-dose focused ion beam (FIB) direct writing of micro-nanostructures and subsequent photoelectrochemical (PEC) etching. The low-dose FIB treatment induces surface negative charge which shields the semiconductor material against PEC etching. Under specific conditions, SCL proves to be a powerful tool for the fabrication of ultrathin GaN suspended membranes which are promising for nanoelectronic applications, in particular in high-power memristive devices [1]. Besides, we demonstrate that SCL provides conditions for the fabrication of GaN ultrathin membranes nanoperforated in an ordered fashion [2]. The development of flexible photonic crystals with embedded waveguides, beam splitters and cavities is reported and the results of modelling of their characteristics are presented. We show also that PEC etching of bulk GaN enables one to fabricate self-organized three-dimensional nanostructured architectures [3]. Results of systematic characterization of the morphology, crystalline quality, electronic and photonic properties of nanoscale-thick gallium nitride membranes along with examples of their practical applications are discussed. [1] M. Dragoman, I. Tiginyanu, D. Dragoman et al., Memristive GaN ultrathin suspended membrane array. Nanotechnology 27, 295204 (2016); [3] O. Volciuc, V. Sergentu, I. Tiginyanu et al., Photonic crystal structures based on GaN ultrathin membranes. J. Nanoelectron. Optoelectron. 9, 271-275 (2014); [3] I. Tiginyanu, M. A. Stevens-Kalceff, A. Sarua et al., Self-organized three-dimensional nanostructured architectures in bulk GaN generated by spatial modulation of doping. ECS J. Solid State Sci. Technol. 5, P218-P227 (2016).

Authors : Jacopo Pedrini,* Christopher Chen, Christoph Kastl, Giuseppe Calafiore, Francesco Meinardi, Stefano Cabrini, Adam M. Schwartzberg
Affiliations : Università degli Studi di Milano-Bicocca, Lawrence Berkeley National Laboratory; Lawrence Berkeley National Laboratory; Lawrence Berkeley National Laboratory; Lawrence Berkeley National Laboratory; Università degli Studi di Milano-Bicocca; Lawrence Berkeley National Laboratory; Lawrence Berkeley National Laboratory

Resume : Photonic crystals (PCs) control light propagation via a photonic band gap, originated when a periodic lattice of alternating refractive index (n) is present. A higher n contrast between the periodic nodes and imbedding medium produces better photonic properties, but the fabrication of large area, homogeneous and high quality PCs is complex due to the poor processability of high-n materials. Transition metal dichalcogenides (TMDs) have a high n (n>3) through the visible and near-infrared spectrum, making them promising for visible light PCs. However, the production of TMD-based PCs is limited by complex chemical interactions in high-resolution etching which reduce the resolution or completely destroy the material. We have developed a new method that does not require the direct etching or processing of TMD to produce TMD-based PCs. The PC structure is etched into quartz (n~1.5), then the TMD is conformally deposited using atomic layer deposition (ALD) to produce a high efficiency PC, The fabricated PC shows intense resonances due to the high n-contrast between the TMD film and the quartz substrate. Moreover, we show that changing the feature size and the thickness of the PC layer can modulate these resonances significantly. This is a new class of 3-D photonic crystal which is simple to fabricate, but produces large optical modulations.

Authors : Seungjun Chung,* Tae-Young Kim, Matin Amani, Geun Ho Ahn, Younggul Song, Ali Javey, Takhee Lee
Affiliations : Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University, Seoul 08826, Korea; Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, United States

Resume : Two-dimensional molybdenum disulfide (MoS2) which is one of the most promising candidates for realizing monolayer (~ 0.65 nm) applications in opto- and nanoelectronics has attracted great interests due to its an excellent transparency in the visible wavelength range, mechanical stiffness, flexibility, and electrical carrier mobility. To meet the growing demand for large-area electronics, synthetic fabrication and electrode patterning methods to produce a large-area monolayer MoS2 semiconductors and contacts, respectively are highly desirable. In this regard, we report the first demonstration of large-area monolayer MoS2 FETs with inkjet-printed Ag source/drain (S/D) electrodes. The monolayer MoS2 film was grown by a chemical vapor deposition (CVD) method, and the top-contact Ag S/D were deposited onto the films using a low-cost drop-on-demand inkjet-printing process without any masks and surface treatments. The electrical characteristics of FETs were comparable to those fabricated by conventional deposition methods such as photo- or electron beam lithography. The contact properties between the S/D and the semiconductor layer were also evaluated using the Y-function method and an analysis of the output characteristic at the low drain voltage regimes. Furthermore, the electrical instability under positive gate-bias stress was studied to investigate the charge-trapping mechanism of the FETs. CVD-grown large-area monolayer MoS2 FETs with inkjet-printed contacts can provide an attractive approach for realizing large-area and low-cost thin-film electronics.

Authors : M. Jiménez-Rodríguez,* A. Núñez-Cascajero, E. Monroy, P. Corredera, Miguel González-Herráez, F.B. Naranjo
Affiliations : GRIFO, Dept. Electrónica, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain; Université Grenoble-Alpes, 38000 Grenoble, France; CEA-Grenoble, INAC-PHELIQS, 17 av. des Martyrs, 38000 Grenoble, France; Instituto de Óptica, CSIC, c/Serrano 144, 28006 Madrid, Spain

Resume : The optical Kerr effect is a nonlinear process present in all materials with applications in domains such as fiber optics communications or integrated photonics. However, it is difficult to find materials with high nonlinear optical properties at telecom wavelengths and high thermal and chemical stability. InN, with band-gap energy in this spectral range, stands out in this field. A simple way to measure the Kerr effect is the z-scan technique, proposed by Sheik-Bahae group in 1990. In this technique, the sample is placed between two achromatic lenses to firstly focus a high peak-power laser beam on the sample and then collimate it to measure the transmitted intensity. The sample transmittance is recorded as a function of its position along the optical axis. This paper presents measurements of the saturable absorption and Kerr effect coefficients in 1-µm-thick InN layers. A mode-locked fiber laser with 200 fs pulses, 4 MHz repetition rate, and 30 mW average power has been used as excitation source. When focused, the laser beam has a Gaussian waist of ?0 ~ 20 µm, a Rayleigh length of z0 ~ 0.5 mm, and a maximum peak intensity of I0 ~ 18 GW/cm2. From z-scan measurements, we estimate a very high nonlinear absorption coefficient of ?2 = 1800 cm/GW and a Kerr coefficient of n2 = 1.5·10-2 cm2/GW. Thus, we can conclude that InN attains nonlinear optical properties suitable for applications at 1.5 µm.

Authors : Su Yong Lee, Hyon Chol Kang*
Affiliations : Pohang Accelerator Laboratory, POSTECH, Pohang 790-834, Republic of Korea;Department of Materials Science and Engineering, Chosun University, Gwangju 501-759, Republic of Korea

Resume : In the last decade, various techniques have been proposed for synthesizing one-dimensional nanostructures such as nanowires (NWs) and nanobelts. In particular, monoclinic gallium oxide (beta-Ga2O3) has received considerable attention for use in NWs owing to its wide bandgap of 4.9 eV, high breakdown field (> 8 MV/cm), and high optical transparency to visible and ultraviolet radiation. Recently, applications of beta-Ga2O3 NWs in optoelectronic and photonic devices, as well as gas sensors, have been widely explored. Moreover, doped beta-Ga2O3 NWs have attracted even greater interest as doping is an effective way to tune the physical properties of such structures. Many of these efforts have focused on demonstrating the performance of NW-based devices by varying the types and concentrations of the doping elements used, with Eu, Cr, Mn, Sn, and In having been examined. Among them, In is regarded as a promising dopant for significantly enhancing the sensitivity and quantum efficiency in nanobelt-based photodetectors, as initially demonstrated by Tian et al., who demonstrated that doping with In atoms increased the carrier density and mobility of Ga2O3 NWs compared to those of their undoped form. The performance of these photodetectors was comparable or superior to that of other one-dimensional semiconductor-based photodetectors. The synthesis of In-doped beta-Ga2O3 NWs is typically carried out by thermal evaporation and vapor transport, using a mixture of either In and Ga2O3 powders or Ga and In2O3 powders as source materials. Recently, we reported the growth of beta-Ga2O3 NWs using radio frequency (RF) powder sputtering. The deposition of non-stoichiometric Ga2O3-x under an oxygen-deficient atmosphere was essential for facilitating the growth of beta-Ga2O3 NWs by a self-catalytic vapor-liquid-solid (VLS) process using self-assembled Ga seeds. In this work, we examine the growth mechanism of In-doped beta-Ga2O3 NWs synthesized by powder sputtering. In particular, the role of In atoms in determining the growth mechanism and the structure of NWs is investigated. Finally, by examining the evolution of surface morphologies as a function of sample thickness, a growth scenario of the In-doped beta-Ga2O3 NWs is proposed.

2D Materials for Functional Applications : Jani Kotakoski
Authors : G. C. Loh, Prof. Dr. Ravindra Pandey*
Affiliations : Michigan Technological University, Houghton MI 49931

Resume : We will report the theoretical results on a layered scandium dioxide (ScO2). Density functional theory calculations under the generalized-gradient approximation with on-site Coulomb interactions (GGA + U) were performed to investigate the stability, electronic and magnetic properties of 2D ScO2. The calculated results find the so-called T-phase to be a non-magnetic wide-band gap semiconductor, and the H-phase monolayer is an antiferromagnetic (AFM) Analysis of the chemical topology shows that the Sc?O bonds are highly ionic in character. Furthermore, T- and H-phase bilayers respond differently to strain applied normal to the material surface; for the former, the band gap increases and then decreases with the increase of tensile strain, whereas the latter shows a metal - semiconductor - metal transition as a larger tensile strain is applied. The versatility of the electronic properties of ScO2 in its different phases and forms (monolayer and bilayer) can thus be exploited in devices at the nanoscale.

Authors : Prof. Dr. Ashutosh Tiwari
Affiliations : Biosensors and Bioelectronics Centre, IFM, Linköping University, 581 83 Linköping, Sweden; Tekidag AB, UCS, Teknikringen 4A, Mjärdevi Science Park, Linköping 583 30, Sweden

Resume : Biodigital devices are emerged an interdisciplinary field of research in the biosensors and bioelectronics [1, 2]. Today, smart bio-interfaces are applying a renewed influence on bioelectronics beyond the incorporation of few or single atom(s)-thick two dimensional (2D) materials, which fuses the benefits of extraordinary stimuli-controlled interior and exterior catalytic atomic surfaces with those of super-thin digital biotechnology [3, 4]. The development of switchable and/or tunable interfaces of 2D materials endowed with desirable functionalities, and incorporation of these interfaces into on/off-switchable bio-devices [5]. The aim of talk is to demonstrate various strategies of stimuli-enabled programming of enzymatic super-thin digital systems answer by a considerable control in their biochemical behavior with uni- and multi-model triggering of interfaces via temperature, pH, light, etc. These smart bioengineered atom-thick approaches are being formulated that sense specific biochemical changes and regulate in a liable manner, making them useful super-thin biotechnological tools. The progress in this field would make significant contributions to new age biodigital energy and medical technologies. References 1. Tiwari, A.; Turner, A. P. F. (Eds.), In Biosensors Nanotechnology, Wiley - Scrivener, USA, MA, 2014. 2. Parlak, O.; Beyazit, S.; Jafari, M. J.; Bui, B. T. S.; Haupt, K.; Tiwari, A.; Turner, A. P. F. Advanced Materials Interfaces, 2015. 3. Parlak, O.; Turner, A

Authors : Dr. Om Prakash Sinha
Affiliations : Amity Institute of Nanotechnology, Amity University, UP, Noida, India

Resume : Stable 2D semiconducting oxide of tungsten and molybdenum has been investigated widely and utilized for several applications. MoO3 2D nano-fakes are found to be of particular interest due to their potential applications. MoO3 nano-fakes have been used for photoluminescence and field emission applications. Bulk MoO3 has been successfully used in organic electronic devices such as organic light emitting diodes (OLEDs) and organic photovoltaics as a hole injection and extraction layer, where the semiconducting properties of MoO3 has improved the efficiencies of these devices significantly. Moving from bulk to 2D nano-fakes is expected to improve the crystalline structure of MoO3, which thereby is expected to improve the semiconducting properties. In continuation to our earlier published work, advantage of 2D materails motivated us to utilize the 2D MoO3 nano-fakes as the hole injection layer (HIL) in OLEDs. Here, to observe the effect of solar illumination on the properties of 2D MoO3 nano-fakes, OLEDs with nano-fakes as the HIL exposed for different durations have been fabricated and their effects on device characteristics are discussed. Nano-fakes irradiated for 0, 15, 30, 45, 60 and 120 min with solar power were used for this study, and the device results with nano-flakes as the HIL were compared with that with bulk MoO3 as the HIL.

Advanced Semiconductor Nanostructuring : Yogendra Kumar Mishra
Authors : Prof. Dr. Jörg Hübner
Affiliations : DTU-Danchip, Technical University of Denmark, Denmark

Resume : Etching of silicon is the basic technology step for a large variety of MEMS, NEMS and microfluidic applications. Even the fabrication of large area nanostructure in polymers starts in our examples with lithography and etching of silicon. After a short introduction to DTU Danchip (Clean Room), the talk will focus on plasma etching of silicon in detail. The plasma chemistry and physics during silicon etching poses challenges and opportunities, which will be demonstrated using examples reaching from nanopillars for SERS enhancement to X-ray compound lenses. A short excursion into Atomic Layer Deposition and some results on structures realized with this very versatile technology will be presented and accordingly discussed. References: 1. Advanced Materials 24, 2012, OP11-OP18 2. Microelectronic Engineering 141, 2015, 6-11 3. Optical Materials Express 5, 2015, 2804-2811

Authors : Mohammad Bashirpour, Jafar Poursafar, Mohammadreza Kolahdouz, Mohammad Neshat,* Hamid Hajhosseini, Morteza Fathipour
Affiliations : ECE Department, School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran

Resume : In the last decade, terahertz technology has attracted attention of researchers and scientists because of its unique properties. Developing reliable sources and detectors are the most prominent part of terahertz technology. Photoconductive antennas are the most common devices for terahertz wave generation and detection due to its compact structure, simple fabrication, room temperature operation and broadband pulse nature. Despite of all advantages, antenna's low output power is the most challenging issue that has to be overcome. In this paper, a photoconductive terahertz source based on periodic nano-plasmonic structure has been introduced, simulated and fabricated. Terahertz power improvement was achieved by periodic nanostructures on the active part of the device. By using finite difference time domain (FDTD) method, periodic gold nanodisk structure has been simulated and optimized for 800 nm femtosecond laser pulse. Laser optical power reflection reduced from 32% for conventional PCA to less than 1% for the designed nanostructure-based antenna. The photocurrent increased more than 100%. Optimized antenna was fabricated on LT-GaAs wafer using photolithography and electron beam lithography methods. Terahertz time domain spectroscopy (THz-TDS) test system confirmed the simulation results and showed output terahertz power improvement.

Authors : Jiuk Jang,* Byung Gwan Hyun, Sangyoon Ji, Eunjin cho, and Jang-Ung Park
Affiliations : School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea

Resume : Recently, transparent heaters require good flexibility and stretchability as the parts of wearable electronics since future smart devices have irregular shapes and arbitrary curved surfaces. Those transparent and stretchable heaters can be applied to diverse areas such as defogging a window, outdoor cooking, and thermal therapy. Although indium tin oxide (ITO) has been widely used as the transparent resistive heater due to its good optoelectronic properties, it has limitations due to its fragility. In addition, the wireless operation becomes essential for the wearable electronics. Here, we demonstrate a large-area transparent and stretchable heater on various substrates based on Joule heating using the random network of the ultra-long Ag nanofibers (AgNFs). Optical transmittance and the sheet resistance of electrode can be controlled by adjusting area fraction of AgNF random networks. Therefore, various temperature range and power consumption can be achieved by varying density of AgNFs. AgNFs heater shows high temperature (250 ºC) at relatively low operating voltage (5.5 V) and excellent temperature reliability under large strain (30%). In addition, we integrated wireless operation system and AgNFs heater. Bluetooth module and the micro-controller unit are connected to AgNFs heater so that temperature can be controlled directly using smart devices. We believe these stretchable and transparent large-area heaters with the wireless operation systems can be embedded into future wearable electronic devices.

Authors : Kai Qian,* Roland Yingjie Tay, Tupei Chen, Edwin Hang Tong Teo, Pooi See Lee
Affiliations : School of Materials Science and Engineering, Nanyang Technological University, Singapore.

Resume : Two-dimensional (2D) layered materials (such as hexagonal boron nitride (hBN) and graphene) bring a new function into nanodevices and flexible electronics due to their excellent mechanical properties. HBN, sometimes referred as ?white graphene?, is a dielectric with a high electrical resistance and a wide bandgap of ~5.9 eV together with chemical inertness and high thermal conductivity, suggesting a myriad of applications in nanodevices ranging from field-effect tunneling transistors, capacitors, to hydrogen storage. Resistive switching memory (RSM) is considered one of the most promising candidates for next generation memory due to its excellent storage capability and scalability down to less than 10 nm. High-performance RSM with excellent mechanical flexibility is of great interest for the future smart wearable electronics. However, conventional switching materials of ceramic dielectric thin films often suffer from detachment from substrates and cracking under repetitive bending, becoming a bottleneck in realizing a highly flexible RSM. In this work, the ultrathin (~ 3 nm) hBN, is synthesized via chemical vapor deposition (CVD) for the fabrication of flexible RSM. The hBN-based RSM features good switching endurance (? 550 cycles), long retention time (? 3000 s) and acceptable memory window (? 100). Especially, the memory device can operate under extreme bending conditions (bending radius, 7 mm) without large variation of memory window, even after 750 bending cycles. Due to the transferable property of hBN like graphene film, the fabrication of transferable hBN-based RSM is promising on any desired arbitrary substrate. This work exploits and broadens the applications of 2D hBN nanomaterial for use as flexible RSM which would be useful in integrated epidermal electronics in future.

Poster Session 2 : Jani Kotakoski, Jost Adam, Yogendra Mishra, Arul Murugan
Authors : S. Biswas, S. Mukherjee, S. Das, S.K. Ray
Affiliations : Department of Physics, IIT Kharagpur, India; Advanced technology development Centre, IIT Kharagpur, India; School of medical science & Technology, IIT Kharagpur, India; Department of Physics, IIT Kharagpur, India

Resume : In recent years, molybdenum disulfide (MoS2) based short-wave optoelectronic devices have drawn a great interest of the scientific communities due to its large direct bandgap in very low dimensions as compared to its bulk counterpart. Researchers have reported several devices using either mechanically exfoliated, or chemically or CVD-grown 2-D mono/multi-layer MoS2 based devices, although the wafer scale device production with very good output performance has not been achieved yet. Therefore, it is desirable to fabricate low-cost and high-responsive devices operating at low powers for better performance. Here, we report the novel MoS2 colloidal quantum dot based photodetector device which exhibits good optical responsivity and detectivity compared to the commercial Si based visible photodetector. The use of colloidal nanocrystal (NC) of 2D materials can be an excellent approach for large area device fabrication as well as a flexible detector with enhanced output due to its excellent light absorbing property of MoS2 NCs and short carrier diffusion path. Moreover, the size-dependent optical characteristics, allowed us to select the desired spectral detection at the time of fabrication by controlling the crystal size, which makes them a potential candidate for tunable optical devices. We have also investigated the potentiality of different sized MoS2 NCs for a wide spectral range using COMSOL simulation based on FEM study which also exhibits the size dependent electric field enhancement and our theoretical predictions matched with the experimental results very well. The current-voltage characteristics and pulsed illumination of all devices have been investigated and reported. Our work demonstrates the great potentiality of the MoS2 NCs based flexible devices where the NCs have been used as the key component for their high performance, low-cost, ease of fabrication and their size-tunable band gap, in the optoelectronic integrated circuits.

Authors : Katia HAMMAR, Leila MESSAD, Abdelhamid ZIANE
Affiliations : Laboratoire de physique et Chimie Quantique, Université Mouloud Mammeri de Tizi-Ouzou, B. P. No. 17 RP, 15000 Tizi-Ouzou, Algeria

Resume : The FePt L10 structure is characterized by a tetragonal distortion of a few percent along the c-axis, accompanied by an alternating stacking of elemental layers along the [001] direction. By means of density functional theory (DFT) calculations, within the pseudopotential plane wave method as implemented in VASP (Vienna Ab initio Simulation Package). The projector augmented wave method with exchange correlation function is used for spin polarized generalized gradient approximation (GGA). We have determined structural, electronic, and magnetic properties of perfect surfaces (9, 11, 13 plans) and with stacking defect. Magnetic properties are determined by: (1) direct Fe-Fe interactions between an Fe atom and its four nearest neighbors in the Fe layer (2.92µB), and (2) polarization driven ?indirect? Fe-Pt-Fe interactions (3.03 µB).

Authors : Leila MESSAD, Katia HAMMAR, Abdelhamid ZIANE
Affiliations : Laboratoire de Physique et Chimie Quantique, Université Mouloud Mammeri de Tizi-Ouzou, B. P. No. 17 RP, 15000 Tizi-Ouzou, Algeria

Resume : Atomic clusters have attracted a lot of attention, and are still a matter of intense research, because of their unique combination of molecular and condensed matter physics. Of particular interest, are the binary clusters composed bimetallic transition metal (TM) clusters with physical and chemical properties. Our investigations are based on spin-polarized density functional theory (DFT) as implemented in the Vienna ab initio simulation package (VASP), with the spin polarized generalized gradient approximation (GGA). The calculations are performed on pure Con and ConCr (n=1-5) clusters, we address how Cr-doping affects the structure, how the binding energy is as compared with the pure clusters, and how electronic properties such as the ionization potential, electron affinity, dissociation energy and magnetic moment, are modified.

Authors : Yoon-Seog Song, Sang-Ouk Ryu
Affiliations : Department of research and development center, NCD Co., Ltd ; Department of electronics engineering, Dankook University,

Resume : An Al2O3 thin films for the purpose of barrier layer against environmental moisture was prepared by means of atomic layer deposition (ALD) method. Moisture in the air is known to be the most responsible element which makes the organic based device unusable. Because most of organic materials are weak at high temperature the thin film process temperature should be maintained as low as possible. To achieve high quality barrier characteristics TMA, TiCl4, H20 were used as precursors and reactant gas and each process conditions were carefully controlled. The Al2O3/TiO2/Al2O3 multilayer thin film was then deposited on PEN substrate. The barrier performance was examined by acquiring a water vapor transmission rate (WVTR) of the thin films.

Authors : Dominik Szczesniak, Ross D. Hoehn
Affiliations : Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar

Resume : The two-dimensional materials (2D) are attracting increasing attention due to their unique properties and potential use in both nano- and opto-electronics. In such applications, the electronic transport properties of 2D materials are particularly important. In this communication, a new insight into these properties is presented by studying the so-called complex band structures (CBSs) of the selected 2D materials (graphene and transition metal dichalcogenide monolayers). We show that the CBSs analysis allows to describe a crucial transport-related phenomena, such as the tunneling currents, electronic state localization, or even the Fermi level pinning in metal-semiconductor junctions. A generalized efficient theoretical method for solving such class of problems is presented and gives a complete set of physically relevant solutions. These solutions are characterized and classified into propagating and evanescent (localized) electronic states, where the latter states present not only monotonic but also oscillatory decay character. Furthermore, the importance of CBS’s for transport processes is additionally reinforced by demonstrating their direct use in the ballistic quantum transport calculations across 2D materials, by using the phase field matching theory.

Authors : Anu Gupta, S. K. Ray, S.K. Srivastava
Affiliations : Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India; Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India ; Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India

Resume : Topological insulators (TIs) have generated a great interest in the fields of condensed matter physics, chemistry and materials science. A topological insulator is a material that is electrically insulating in the bulk, while possessing highly conductive and spin-polarized massless Dirac surface states that are protected against disorder by time-reversal symmetry (TRS), allowing for near dissipation-less transport of spin on the surface[1]. The TRS can be broken by, for example, using elemental doping to induce a magnetic phase in the material. The broken time-reversal symmetry allows for the formation of an energy gap on the surface and is important for many interesting properties in these materials [2]. The second generation 3D Tis Bi_2 Se_3 and Bi_2 Te_3 are a class of such materials. To enable a multitude of possible applications of these materials, it is necessary to open a surface energy gap as well as keep the Fermi energy inside the bulk gap [3]. It has been proposed in the literature that doping TIs by magnetic transition metals, such as Fe, Mn, Cr and Co, could break the TRS and open a surface gap [4]. The binary compound Bi_2 Se_3 is very popular compound for TI studies as it has a relatively large bandgap ( ̴ 0.3 eV) compared with other TIs. Transition metals, such as Fe, Cr, Mn, and Cu have been widely substituted into bulk Bi_2 Se_3 to produce magnetically manipulated topological semiconductors [5]. One attractive direction in the research is the use of nanostructures, wherein the ratio of surface area to volume is much higher than in bulk materials so that the total conduction from the bulk region is lower, allowing observation of the surface states in certain transport measurements. In the present study, we synthesized Co-doped Bi_2 Se_3 nanoplates by solvothermal reaction. The as-synthesized nanoplates show uniform hexagonal morphology of about 1 μm size and ~ 30 nm thickness. A physical property measurement system (PPMS) is used to determine the temperature dependent magnetization in zero-field cooled and field-cooled cycle between 5 K and 300 K. The doped nanoplates are found to be paramagnetic in the whole temperature range, in disagreement with the existence of a diamagnetic to paramagnetic phase transition at 12 K in Co-doped Bi_2 Se_3 single crystals. Further experimental and computational studies of electronic and magnetic properties of the system are under way. References: [1] M. Z. Hasan and C. L. Kane, Rev. Mod. Phys. 82, 3045 (2010). [2] J. Wang, X. Chen, B.-F. Zhu, and S.-C. Zhang, Phys. Rev.B 85, 235131 (2012) [3] X. L. Qi, T. L. Hughes, and S. C. Zhang, Phys. Rev. B 78, 195424 (2008) [4] Q. Liu, C. X. Liu, C. Xu, X. L. Qi, and S. C. Zhang, Phys. Rev. Lett. 102, 156603 (2009). [5] Y. S. Hor, A. J. Williams, J. G. Checkelsky, P. Roushan, J. Seo, Q. Xu, H.W. Zandbergen, A. Yazdani, N. P. Ong, and R. J. Cava1, Phys. Rev. Lett. 104, 057001 (2010).

Authors : Arif Kösemen, Zühal Alpaslan Kösemen, Sadullah Öztürk, Betül Canımkubey, Mustafa Erkovan, Yusuf Yerli, Ali Veysel Tunç
Affiliations : Arif Kösemen; Department of Physics, Muş Alparslan University, Muş, Turkey Mustafa Erkovan; Zühal Alpaslan Kösemen;Department of Physics, Gebze Technical university, Kocaeli, Turkey Zühal Alpaslan Kösemen; TUBİTAK UME Optics Laboratory, 41470 Gebze, Kocaeli, Turkey Sadullah Öztürk; Enginnering Department, Fatih Sultan Mehmet Vakif University, 34080 Istanbul, Turkey Betül Canımkubey; Deparment of Physics, Amasya University, Amasya, Turkey Yusuf Yerli; Department of Physics, Yıldız Technical University, Davutpaşa, Turkey Ali Veysel Tunç; Department of Energy Systems Engineering, Istanbul Bilgi University, 34060, Eyup, Istanbul, Turkey

Resume : Photoresponsive organic field-effect transistors (Photo-OFETs) and Photodiodes have been widely investigated because of their attractive advantages such as large-area, flexibility, and processing versatility [1-3]. Single organic layer, organic planar heterojunctions and bulk heterojunctions thin film are widely used in phototransistors [4-5]. Nevertheless, the photoresponsivity of single organic layer photo-OFETs is generally low due to the relatively low charge carrier mobility of the active semiconductor layer and poor exciton dissociation efficiency. In this study, we present on the fabrication of phototransistors with a novel multilayer organic planar junction structure, in which the photo excitons generation and dissociation are realized mainly in all the organic semiconductor layers P3HT/CuPc/P3HT, while the transport of charge carrier current occurs in high mobility channel layer based on P3HT. We fabricated P3HT/CUPC photo-OFETs on glass substrates. The electrodes were etched with standard photo lithography to produce interdigitated source-drain electrode fingers with a channel length of 100 µm and a channel width of 60mm. Three different device structures was fabricated in this study and named as D1, D2, D3, configurations are given below; D1: Au (S-D)/P3HT(100nm)/PMMA(600nm)/Al(gate), D2: Au (S-D)/CuPc(10nm)/P3HT(100nm)/PMMA(600nm)/Al(gate), D3: Au (S-D)/P3HT(100nm)/CuPc(10nm)/PMMA(600nm)/Al(gate), Table 1: Device performance details Devices R (mA/W) Max. value of P Vth µDark (cm2/Vs) µLight (cm2/Vs) D1 14.25 (VG=-40V) 5.95 x 10^2 -7.5 0.002 0.002 D2 34.74 (VG=-40V) 2.1 x 10^3 -5.11 0.0015 0.0014 D3 11.58 (VG=-40V) 1.3 x 10^3 0.62 0.00028 0.00024 References: 1) Y. Chu, X. Wu, J. Lu, D. Liu, J. Du, G. Zhang, J. Huang, Adv. Sci. 1500435 (2016). 2) Z. A. Kösemen, A. Kösemen, S. Öztürk, B. Canımkurbey, S. E. San, Y. Yerli, A. V. Tunç, Microelectronic Engineering 161, 36–42 (2016). 3) Y. Li, W. Lv, X. Luo, L. Sun, F. Zhao, J. Zhang, J. Zhong, F. Huang, Y. Peng, Organic Electronics, 26, 186-190 (2015). 4) Y. Guo, G. Yu, Y. Liu, Adv. Mater., 22, 4427–4447, (2010). 5) J.G. Labram, P.H. Wökenberg, D.D.C. Bradley, T.D. Anthopoulos, Org. Electron., 11, 1250–1254 (2010).

Authors : Shweta Sareen, Vishal Mutreja, Satnam Singh and Bonamali Pal
Affiliations : Shweta Sareen; School of Chemistry & Biochemistry, Thapar University, Patiala-147004, Punjab, India Vishal Mutreja;Department of Chemistry, Maharishi Markandeshwar University, Mullana, Ambala-133207 Satnam Singh; School of Chemistry & Biochemistry, Thapar University, Patiala-147004, Punjab, India Bonamali Pal;School of Chemistry & Biochemistry, Thapar University, Patiala-147004, Punjab, India

Resume : Bimetallic systems of Au-Ag nanostructures were synthesized within the channels of amine modified mesoporous SBA-15 by post modification. It was found that the mesoporous channels effectively controlled the changes in the size and morphology of the embedded nanoparticles from spherical (6-8 nm) to rod shape (aspect ratio ~15-20 nm) with variation in the amount of bimetallic (Au and Ag) loading. The change in the color of the prepared materials from white for bare SBA-15 to deep purple for Au-Ag (10:1) loading and dark brown for Au-Ag (1:10) loading established the inclusion of metals within the mesoporous sieves. EDX and elemental mapping studies confirmed the presence of Au and Ag nanospecies within/on the surface of silica hosts. DRS studies showed the presence of single plasmon band for various bimetallic Au-Ag loadings illustrating the alloy structure/nature of NPs with homogeneous composition. TEM micrographs depicted discrete bimetallic nanostructures uniformly distributed and stabilized within/on the surface of mesoporous host. Moreover, surface area was significantly reduced from 694 m2g-1 for bare SBA-15 to 484 and 533 m2g-1 for Au-Ag (1:10) and Au-Ag (10:1) loading respectively due to partial blocking of mesopores with increased bimetallic impregnation. The prepared bimetallic composites also exhibited unprecedently high catalytic activity due to the combined tuning of high particle dispersion and enhanced synergy. Among all bimetallic nanocomposites, Au-Ag (5:1)/m-SBA-15 nanocomposites exhibited the best catalytic activity (k= 2.12×10-2 min-1 and 3.99×10-2 min-1) in comparison to other bimetallic and monometallic Au/m-SBA-15 and Ag/m-SBA-15 nanocomposites for the selective reduction of nitrobenzene to aniline and p-nitroacetophenone to p-aminoacetophenone respectively.

Authors : Dong-Hyeon Seo, Chung-Hyo Lee
Affiliations : Department of Advanced Materials Science and Engineering, Mokpo National University

Resume : Half-metallic ferromagnets (HMFs) have attracted considerable attention due to their potential use as a highly spin-polarized current source in spintronics. Among some kinds of HMFs, Co-based full Heusler alloys are of particular interest due to comparatively high Curie temperatures. For applications, not only a high Curie temperature and high spin polarization but also high stability of the L21 phase is desired. In the present work, a mixture of elemental Co50Mn25Al25 powders has been subjected to mechanical alloying (MA) to prepare the Heusler Co2MnAl magnetic alloys. It is found that nanocrystalline Co2MnAl alloys with a grain size of 80 nm can be produced from a mixture of elemental Co50Mn25Al25 powders by MA for 5 hours coupled with subsequently annealed at 700C. The X-ray diffraction and magnetic data have been discussed simultaneously in order to achieve a better understanding of the solid state reaction induced by MA. Acknowledgements This work is financially supported by the Ministry of Knowledge Economy (MKE) of Korea.

Authors : A. Nikolov, T. Koutzarova, R. Nikov, N. Nedyalkov, P. Atanasov, S. Kolev, P. Peneva, D. Karashanova, D. Kovacheva, J.W. Gerlach, B. Rauschenbach
Affiliations : 1 Institute of Electronics, Bulgarian Academy of Sciences, Tzarigradsko Chaussee 72, Sofia 1784, Bulgaria 2 Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Building 109, 1113 Sofia, Bulgaria 3 Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., bld. 11, 1113 Sofia, Bulgaria 4 Leibniz Institute of Surface Modification (IOM), Permoserstrasse 15, D-04318 Leipzig, Germany

Resume : The method of nanosecond pulsed laser ablation in liquid environment is employed to produce nanostructures. The disc-shaped barium hexaferrite ablation target is fabricated by sol-gel auto-combustion and embedded in double distilled water during the experiment. The ablation procedure is performed by a Nd:YAG laser system. Different colloids are fabricated by variation of the laser wavelength and fluence. Their influence on the morphology of the nanostructures produced is investigated. The fundamental (? = 1064 nm), second (? = 532 nm), third (? = 355 nm) and fourth (? = 266 nm) harmonic and fluence changed from several J/cm2 to tens of J/cm2 are used at the experiments. The effectivity of the ablation procedure is estimated by the optical transmission of the colloids in the near UV and visible regions. The shape of the nanostructures and their size distribution are visualized by using TEM analysis. XRD, SAED and HRTEM are applied to examine the material phases of the nanostructures obtained. The nanoscale magnetic ferrites are of particular interest due to the unique combination of electronic and magnetic properties and their chemical compatibility with biological tissues.

Authors : Mukesh Tripathi1, Roland Kozubek2, Maria O?Brien3, Ursula Ludacka1, Lukas Madauß2, Niall McEvoy3, Toma Susi1, Georg S. Duesberg3, Marika Schleberger2, Jani Kotakoski1
Affiliations : 1 Faculty of Physics, Boltzmanngasse 5, University of Vienna,Vienna 1090, Austria 2 Facultät für Physik, Universität Duisburg-Essen, Lotharstrasse 1, 47057 Duisburg,Germany 3 School of Chemistry and AMBER centre, Trinity College, Dublin 2, Ireland

Resume : Structural defects can drastically alter the electronic and other properties of 2D materials such as molybdenum disulfide (MoS2). Here, we present an atomic-level analysis of ion irradiation-induced defects in MoS2. Highly homogeneous MoS2 flakes over large areas were synthesized using the chemical vapor deposition (CVD) in a microreactor. To transfer the samples onto TEM grids, carbon coated Quantifoil TEM grids were placed onto the MoS2 flakes on silicon oxide substrates and adhered by evaporation of drops of isopropanol. The silicon dioxide layer was then etched using potassium hydroxide (KOH) to detach the TEM grid along with the MoS2 flakes. The grid was then transferred through water into isopropanol and dried. For introducing defects, the samples were irradiated by highly charged (20?40 ) Xe ions, with fluences between 2000 and 10000 ions/µm2. The atomic structure of the defects (mainly holes) was then analyzed using an aberration-corrected scanning transmission electron microscope (Nion UltraSTEM100) operated at 60 kV. The edge structure of the holes is studied at the atomic level and the number of created defects is correlated with the irradiation fluences. Similarly, the size distribution of the created holes is compared to the charge state of the ions. Due to the typical defect type (a triangular hole), MoS2 membranes exposed to ion irradiation may find applications in fields such as filtration and DNA sequencing.

Authors : Won Seok Choi, Hyun jin Cho, Yong hee Lee, Moo hyun Kim, Duk young Jeon*
Affiliations : Korea Advanced Institute of Science and Technology (KAIST)

Resume : 1-D quantum rod has shown extremely reduced photoluminescence (PL) intensity under the E-field, because of relatively easy carrier separation, and this phenomenon is called PL quenching and recovery (on/off characteristic). Using the on/off characteristics, quantum rods can be utilized as an emitting material for future display. CdZnS/ZnS (core/shell) structure has attracted attentions due to high PL quantum yield (PL QY) and purity of blue light (440~461 nm). So, CdZnS/ZnS structure is proper to demonstrate high quality blue emitting materials. However, this structure has problem of low on/off characteristic due to difference in valence band edge between core and shell. To solve this problem, we decided to dope ZnS with nitrogen as a p-type dopant for hole transport from core to shell. In previous reports, hole conductivity significantly increases by p-type doping. The dopant should be dispersed uniformly in the shell because doping can help transfer of hole. Therefore, we developed in-situ method which help both growth of ZnS and N doping at the same time. This method can demonstrate not only uniform doping but also optimizing peak shift. So far, we obtained peak shift (from core peak) of below 6 nm and on/off characteristic of below 70 %.

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Fundamental Properties of Nanomaterials : Jani Kotakoski
Authors : Dr. Santosh KC,* Roberto C. Longo, Robert M. Wallace, Kyeongjae Cho
Affiliations : Materials Science and Technology Division, Oak Ridge National Laboratory, Bethel Valley Road, Oak Ridge, Tennessee 37831, USA; Department of Materials Science & Engineering, The University of Texas at Dallas, Richardson, TX 75080

Resume : Layered transitional metal dichalcogenides (TMDs) have emerged as potential alternative channel materials for ultra-thin and low power nanoelectronics and opto-electronics devices. Highly tunable and unique electronic properties of TMDs made them promising novel materials for various other applications as well. However, in order to realize the superior performance of devices based on TMDs, the physical and chemical properties need to be understood, in particular, their defect chemistries and stabilities under various chemical environments. In order to facilitate the experimental efforts, it would be helpful to examine the atomic level insights on the properties of TMDs from first-principles calculations. In this talk, I will present our research on the defect structures, oxidation, and corresponding electronic properties of TMDs as well as its interfaces, such as MoS2/HfO2 or MoS2/MoO3. In addition, the effects of the dielectric environment on the electronic and optical properties of single layer TMDs will be discussed. Moreover, the impact of various interfacial defects on electronic properties will be included, which in fact helps to simulate the realistic interfacial phenomenon and optimize the properties of the semiconducting devices.

Authors : Prof. Dr. Sanjeev K. Srivastava
Affiliations : Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India

Resume : Thermal phase transitions, usually triggered by fluctuations caused by tuning the temperature close to a critical temperature Tc, are very familiar daily phenomena. As the temperature is lowered, thermal fluctuations decrease and eventually cease at T = 0 K. However, quantum fluctuations do not stop at 0 K. If the Tc can be brought to zero by a non-thermal parameter at a critical value, then these quantum fluctuations trigger the so-called quantum phase transitions (QPT). Certain bulk binary alloys, like PdxNi1-x [1], VxNi1-x and RhxNi1-x, are reported to possess a QPT near a critical concentration xc. In the vicinity of xc, the material shows non-conventional properties, like non-Fermi liquid behavior and quantum Griffiths phase (QGP). Further, these quantum critical phenomena are known to intricately relate with the shape of the Fermi surface. Materials at nanoscale, which have somewhat discrete nature of electron densities of states, supposedly have their Fermi surfaces different from the corresponding bulk. So, the alloys showing QPT in bulk may or may not have these transitions at nanoscale. It is, thus, quite intriguing to explore the existence of QPT in these alloy nanoparticles. In this talk, our recent results on the existence of resistivity anomaly associated with a QPT in PdxNi1-x nanoalloys [2] and the evidence of a QGP in VxNi1-x nanoalloys [3] will be presented. The on-going work on the exploration of QPT in RhxNi1-x, nanoalloys will also be discussed briefly.

Authors : N. Arul Murugan
Affiliations : Virtual Laboratory for Molecular Probes and Smart Materials Division of Theoretical Chemistry and Biology School of Biotechnology Royal Institute of Technology S-10639, Stockholm, Sweden

Resume : Materials with stimuli responsive properties and binding affinity towards specific biomolecular entities have wide range of applications in health-care. Understanding the mechanism behind their ability to recognize (bio)molecules and their target specific spectroscopic properties can pave the way to design effective and improved molecular probes, tracers and drug molecules for the purpose of selective diagnosis of various diseases and the therapeutics[1-2]. However, the computational modeling of these materials pose enormous challenges due to their complex nature and associated larger length and time scales. It also becomes computationally very demanding since we need to explicitly describe the electronic degrees of freedom and the heterogeneous environment. Here, we discuss about some sophisticated modeling strategies based on the hybrid quantum mechanics/molecular mechanics methodlogy to model various aspects of these smart materials such as their environment specific changes in molecular geometry and electronic structure, biomacromolecular recognition and their target specific spectroscopic properties[3-8]. Referenences [1] E.D. Agdeppa, M.E. Spilker, The AAPS Journal 11(2), 286(2009). [2] W. E. Klunk, H. Engler, A. Nordberg, Y. Wang, G. Blomqvist, D. P. Holt, M. Bergstrom, et al., Annals of neurology 55, 306(2004) [3] N. Arul Murugan, J. Kongsted, Z. Rinkevicius, and H. Agren, Phys. Chem. Chem. Phys. (Comm.) 14, 1107(2012). [4] N. Arul Murugan, R. Apostolov, Z. Rinkevicius, J. Kongsted, Erik Lindahl and H. Agren, J. Am. Chem. Soc. 135(36), 13590(2013). [5] N. Arul Murugan, Magnus, J. Kongsted, Z. Rinkevicius, K. Aidas and H. Agren, J. Phys. Chem. Lett. 4, 70(2013). [6] N. Arul Murugan, J. Kongsted and H. Agren, J. Chem. Theory Comput. 9(8), 3660(2013). [7] N. Arul Murugan, R. Zalesny, J. Kongsted and H. Agren, J. Chem. Theory Comput. 10(2), 778(2014). [8] N. Arul Murugan, C. Halldin, A. Nordberg, B. Langstrom, H. Ågren, J. Phys. Chem. Lett, 2016.

Authors : Paramita Patra,* S. A. Khan, D. Kabiraj, Manju Bala, D. K. Avasthi, S. K. Srivastava*
Affiliations : Department of Physics,Indian Institute of Technology Kharagpur, Kharagpur 721302, India; Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067, India; Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067, India; Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067, India; Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067, India; Department of Physics,Indian Institute of Technology Kharagpur, Kharagpur 721302, India

Resume : Irradiation of thin films with energetic ions often leads to atomic displacements due to the ion-matter interaction,resulting in an intermixing of the film with its substrate.In the case of swift heavy ions (SHIs), the occurrence of thermal spikes via electron-phonon coupling (EPC) mediated transfer of electronic energy to lattice [1,2] has been identified as the primary cause of all observed SHI-matter interaction related phenomena.In order to estimate or predict the effect of SHI irradiation quantitatively, the EPC factor has so far been taken to be constant equal to the electron density of states (eDOS) at Fermi energy according to the free-electron theory of metals. However, in metals the electrons are under a highly non-equilibrium process and the calculation of EPC factor requires exact eDOS, which can be computed from density functional theory (DFT) [3]. Based on the above concept, we calculated composition-dependent EPC strength for a series of complete solid soluble Pd1-xNix alloys by computing their eDOSs using full-potential linearized augmented plane wave method of DFT and indeed found an x-dependence of EPC strength for the alloy system. In order to see its effect on SHI-matter interaction, we prepared these alloys on Si substrates, irradiated these with 100 MeV Au ions at 1× 10^14 ions/cm^2, and monitored the diffusions of Pd and Ni independently in Si for each case. Although the Rutherford backscattering spectra do not show any intermixing possibly due to the poor spatial resolution of the technique, the depth profiles using X-ray photoelectron spectroscopy show a considerable mixing of Pd and Ni in Pd/Si and Ni/Si systems, respectively, right after the SHI irradiation, an observation not reported earlier for these systems. Further, for an intermediate composition Pd0.23Ni0.77, the mixing efficiencies of Pd and Ni both in Si is found to be an order of magnitude less than those of pure elements. This is in complete agreement with the notion that the EPC factor must be calculated using eDOS, rather than taking as a constant, and thus supports the thermal spike model of SHI-matter interaction. References 1. Z.G. Wang, C. Dufour, E. Paumier and M. Toulemomde, J. Phys: Condensed Matter, 6 (1994) 6733 2. S.K. Srivastava,, D.K. Avasthi, W.Assmann,Z.G. Wang, H. Kucal, E. Jacquet, H.D. Carstanjen,and M. Toulemonde, Phys. Rev. B 71 (2005) 193405. 3. Z. Lin, L.V. Zhigilei, and V. Celli, Phys. Rev. B 77 (2008) 075133.

Nanophosphors and 2D Materials : Arul Murugan
Authors : Prof. Dr. Mikhail Brik,* A.M. Srivastava
Affiliations : College of Sciences, Chongqing University of Posts and Telecommunications, Chongqing 400065, People?s Republic of China Institute of Physics, University of Tartu, W. Ostwald Str. 1, Tartu 50411, Estonia Institute of Physics, Jan Dlugosz University, PL-42200 Czestochowa, Poland; GE Global Research, One Research Circle, Niskayuna, New York 12309, USA

Resume : Spectroscopic properties of crystalline materials doped with the Mn4+ ions are intensively studied, both experimentally and theoretically, because of their applications for solid state lighting, holographic recording, optical data storage, dosimetry etc. These systems have been an object of our thorough investigations over several recent years [1-7 and references therein]. In the present work a particular emphasis is placed on calculations of the Mn4+ energy levels in solids by using crystal field and ab initio methods. An analysis of spectroscopic properties of Mn4+ ions allowed to establish correlation between the energy of the 2Eg?4A2g red emission transition (that is of growing importance in white LED technology) and degree of covalency of the ?Mn4+ - ligand? chemical bonds, which is determined by the degree of reduction of the Racah parameters of Mn4+ ions in solids in comparison with those for a free state. Several practical recommendations on how to tune the Mn4+ red emission are suggested. References: [1] A.M. Srivastava, M.G. Brik, J. Lumin. 132 (2012) 579. [2] M.G. Brik, A.M. Srivastava, J. Lumin. 133 (2013) 69. [3] M.G. Brik, A.M. Srivastava, Opt. Mater. 35 (2013) 1251. [4] M.G. Brik, A.M. Srivastava, ECS J. Solid State Sci. & Technol. 2 (2013) R148. [5] M.G. Brik, S.J. Camardello, A.M. Srivastava, ECS J. Solid State Sci. & Technol. 4 (2015) R39. [6] M.G. Brik, S.J. Camardello, A.M. Srivastava, N.M. Avram, A. Suchocki, ECS J. Solid State Sci. & Technol. 5 (2016) R3067. [7] M.G. Brik, A.M. Srivastava, Opt. Mater. 54 (2016) 245.

Authors : Prof. Dr. Ashutosh Tiwari
Affiliations : Department of Materials Science and Engineering University of Utah, Salt Lake City, Utah 84112, USA

Resume : Spintronics represents a new paradigm of electronics that utilizes both the electron’s charge as well as its spin degrees of freedom. It has the potential to facilitate a new generation of devices possessing high-speed, large memory and ultra-low power consumption. The most critical step in the functioning of a spintronic device is the injection and detection of spin-polarized carriers at the ferromagnet-semiconductor interface. Despite considerable efforts, efficient injection of spins into nonmagnetic semiconductors still continues to be a major hurdle in this field. All the possible routs of injecting spin in semiconductors rely on oxides. In this talk, I will present some of our very exciting research going on in this field in my group at the University of Utah. Particular focus will be on the injection and detection of spin polarized carriers in semiconductors using electrical and thermal routes. In the later part of my talk, I will also discuss about a new oxide-based 2D material system discovered in my laboratory very recently.

Authors : S. Osella,* N. A. Murugan, H. Ågren, S. Knippenberg
Affiliations : Division of Theoretical Chemistry and Biology, KTH Royal Institute of Technology, Stockholm, Sweden

Resume : The fluorescent marker Laurdan (6-lauroyl-2-(N,N-dimethylamino)naphthalene), and its new derivative, C-laurdan (6-dodecanoyl-2-[N-methyl-N-(carboxymethyl)amino]-naphtalene), have been investigated in a DOPC lipid bilayer and a comparison is made with results from fluorescence experiments. Experimentally, the latter probe is known to have a higher sensitivity to the membrane polarity at the lipid head-group region and has higher water solubility [1]. Molecular dynamics (MD) simulations are used to study the position of the fluorescent probe in the membrane, which might differ along with the membrane phase. Dependent on the temperature, the gel (S0), liquid ordered (Lo) or liquid disordered (Ld) phases are considered. Results from MD simulations show that Laurdan is oriented with the carbonyl group towards the head of the membrane, with an angle of ca. 70-80° between the molecular backbone and the normal to the bilayer, while C-laurdan presents an angle of 50°, with opposite orientation than for Laurdan. This different orientation will reflect the difference in transition dipole moment between the two probes and, in turn, the different optical properties. Preliminary QM-MM results of the probe in water show little differences in absorption spectra, while the second harmonic generation (SHG) beta component is twice as large in Laurdan with respect to C-laurdan probe. Other two probes, namely a new BODIPY-based membrane probe (BNP) [2] and DiI-C18 are described and compared. The latter one can be excited in the red spectral region, while the previous one can be pinpointed to the blue part. MD simulations of BNP in a model of the DOPC bilayer indicate that the average angle of the transition moments with respect to the membrane normal is ca. 70o, which is comparable with the value reported for DiI-C18. The affinity of both probes for different phases (Ld DOPC, DPPC in both S0 and Ld phases and Lo phase of a 2:1 mixture of Sphingomyelin and Cholesterol) are studied by Gibbs free energy profiles calculation. To investigate the influence of the different phases on the (non-) linear absorption spectra of the probes, benchmark calculations are performed using CC2 and higher order ADC methodologies. Comparison is made with TDDFT and diverse functionals. A multiscale integrated approach is further on used to assess the optical properties in both membrane and water environment, using a polarizable embedding QM/MM formalism implemented in the Dalton package of programs. One and two photon absorption spectra are investigated and the first hyperpolarizability is calculated. [1] J. Barucha-Kraszewska, S. Kraszewski, C. Ramseyer, Langmuir, 2013, 29, 1174. [2] M. Bacalum, L. N. Wang, S. Boodts, P. Yuan, V. Leen, N. Smisdom, E. Fron, S. Knippenberg, G. Fabre, P. Trouillas, D. Beljonne, W. Dehaen, N. Boens, M. Ameloot, Langmuir, 2016, 32, 3495?3505.

Authors : Suwat Nanan,* Paramin Tanyapoo, and Poomsith Thangsan
Affiliations : Materials Chemistry Research Center, Department of Chemistry and Center of Excellent for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand

Resume : Five semiconductors namely ZnS, ZnO(S1), ZnO(S2), CdO and CuS have been synthesized by chemical precipitation method. After that the composites based on dispersion of the semiconductors in 4?-(hexyloxy)-4-biphenyl-carbonitrile 96% (HOBC) nematic liquid crystal have been prepared by melt-mixing method. The four composites namely ZnO(S1)/HOBC, ZnO(S2)/HOBC, CdO/HOBC and CuS/HOBC have been investigated. Confirmation of chemical structures from XRD patterns found that ZnS shows cubic zincblende structure while ZnO(S1) and ZnO(S2) exhibit hexagonal wurtzite structure. CdO belongs to face centred cubic (fcc) structure and CuS shows hexagonal structure. On examining band gap energy of semiconductors by Tauc?s plots from UV/Vis spectra, it was found that ZnO(S1) shows enhancement of band gap energy with increasing calcination temperature. The ZnO(S2) sample, which calcined at various temperatures, exhibits a peak of UV/Vis spectrum at 348 nm. The UV/Vis spectrum of CdO which calcined at 400oC shows absorption edges at 295 nm (4.2 eV) and 540 nm (2.30 eV) due to the formation of CdO during calcination (540 nm) and the partial remaining of CdS (295 nm), respectively. The thermal stabilities of semiconductors have been studied by using Thermogravimetric analysis (TGA) method. ZnO(S1) and ZnO(S2) show two decomposition steps namely the weight loss at 100-200oC and the weight loss at higher than 550oC which due to the loss of water and the decomposition of ZnO, respectively. CdO shows weight loss at about 250-450oC while CuS exhibits weight loss at about 180-300oC. Almost all composites show improvement of thermal stabilities with increasing calcination temperature. The morphology of ZnO(S2) which investigated by scanning electron microscopy (SEM) shows spherical particle of about 67-167 nm. The composites show clearing temperature (TNI), determined from DSC thermograms, at about 78.0oC which closed to that of pure HOBC matrix. In the case of ZnO(S1)/HOBC composite, addition of 5wt% ZnO shows increasing of intensity in PL spectrum in comparison to that of neat HOBC. These PL spectra of composites also show blue shift with increasing semiconductor content. Interestingly, in the case of ZnO(S2)/HOBC composite there was additional peak at 424 which due to PL of ZnO. The lowering of the peak intensity at 358 nm with increasing of ZnO(S2) content was also observed. In contrast, in the case of CdO/HOBC composite, addition of CdO content results in higher PL intensities of composites in comparison to neat HOBC matrix. There was a shift of peak toward lower energy, i.e. red shift with increasing CdO content. Finally, in the case of CuS/HOBC composite, the PL spectra of composites exhibit lowering of PL intensity with enhancement of CuS content up to 15wt%. References [1] J.S. Roy, T. Pal Majumder, R. Dabrowski, J. Mol Structure. 1098, 351-354 (2015). [2] M. Mashra, R. S. Dabrowski, R. Dhar, J. Mol Structure. 213, 247-254 (2016).

Authors : E. S. Nour,* A. Bondarevs, P. Huss, M. Sandberg, S. Gong, M. Willander, O. Nur
Affiliations : Department of Science and Technology (ITN), Campus Norrkoping, Linköping University, SE-60 174 Norrkoping, Sweden; Printed Electronics, Acreo AB, P.O. Box 787, 60117 Norrköping, Sweden

Resume : Harvesting energy from irregular/random mechanical actions in variable and uncontrollable environments is an effective approach for powering wireless mobile electronics to meet a wide range of applications in our daily life. In this work, we design and fabricate a paper-based nanogenerator (NG) utilizing piezoelectric zinc oxide nanowires (ZnO NWs) grown hydrothermally on a paper substrate. The fabricated NG is capable of harvesting ambient mechanical energy from various kinds of human motions, such as footsteps. The generated electric output from a single ZnO NWs/PVDF-TrFE NG has been used to serve as low frequency self-powered triggering sensor. Using the demonstrated piezoelectric foot-step sensor, a wireless transmission was operated successfully.

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Plasmonics & Hybrid Materials : Jost Adam
Authors : Prof. Dr. Dong Ha Kim
Affiliations : Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea

Resume : Plasmonics have been recognized as a promising platform that may premise the performance enhancement of diverse optoelectronics. Representative examples include the exploitation of plasmonic nanostructures for photovoltaic devices, photodectors, and optical biosensors. It is noted that a universal paradigm to construct high-efficiency plasmonic solar cells with long term stability has not been established. Here, we propose a few strategies to develop viable plasmonic dye-sensitized solar cells and organic photovoltaic devices based on the integration of metal-graphene oxide core-shell nanostructures or lithographically-induced plasmonic nanopatterns. The development of highly sensitive and selective photodectors has been an interesting issue yet to be resolved, for which we introduce a simple protocol for the fabrication of wavelength-selective photodiodes utilizing shape-controlled noble metal nanoparticles. Surface plasmon based optical biosensors constitute a well-established model that efficiently realized the activity of plasmonics for viable optoelectronics. We discuss plasmonic-coupling based concepts to develop optical biosensors with enhanced functions.

Authors : A. Platonenko,* D. Bocharov, S. Piskunov, Yu.F. Zhukovskii, E. Spohr, P.N. D’yachkov
Affiliations : Institute of Solid State Physics, University of Latvia, Kengaraga Street 8, LV-1063 Riga, Latvia; Department of Theoretical Chemistry, University of Duisburg-Essen, Essen D-45141, Germany; Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii Prosp. 31, Moscow 119991, Russia

Resume : Water splitting under solar irradiation is a clean and renewable source for hydrogen fuel production. Major limitation for sunlight conversion relates to the band gaps of semiconducting photocatalysts (visible light excitations correspond to their widths 1.5-2.8 eV). Proper band alignment relative to both reduction (H+/H2) and oxidation (O2/H2O) potentials (4.44 eV and 5.67 eV, respectively) is required too. Doping of photocatalysts leads to appearance of induced levels in their band gaps, thus creating new optical absorption edges. It decreases energy threshold, and visible light photons become capable of overcoming the gap. Using first principles approaches within the density functional theory (DFT) based on either localized Gaussian basis functions at linear combination of atomic orbitals (LCAO) or linear augmented cylindrical waves (LACW), we perform comparative study of titania nanotubes (NTs) with fluorite morphology, which are found to be promising 1D photocatalysts for water splitting in visible light spectra. For simulations, we consider titania nanotubes with armchair (4,4) chirality, certain part of Ti atoms in which are substituted by Sc, V, Cr, Mn, Fe, Co, Ni, Cu or Zn dopants. Obtained results allow us to predict that among modified fluorite-structured TiO2 NTs Sc-doped NT are the most promising for hydrogen fuel production. Various co-doped schemes for efficient visible-light-driven water splitting using combination of 3d-metal dopants are also considered

Authors : John A. Scott,* Toan Trong Tran, Daniel Totonjian, Jinghua Fang, Igor Aharonovich, Andrew McDonagh, Milos Toth and Charlene Lobo
Affiliations : School of Physics and Advanced Materials, University of Technology, Sydney, P.O. Box 123, Broadway, New South Wales 2007, Australia

Resume : Metal nanowires are building blocks for realizing new devices with applications in optoelectronics, spintronics, biosensing and medicine, as well as in catalysis, motors, and drug delivery[1-4]. Metal nanowires also enable fundamental studies of ballistic transport and of the effect of dimensionality on phenomena such as spin and orbital momentum and magnetic anisotropy[5,6]. However high quality, high density single crystalline materials have been surprisingly difficult to fabricate. Here we report a versatile, template-free method for fabrication of single crystalline metal and metal alloy nanowires (Co, Ni, NiCo, CoFe, and NiFe) by reduction of metal nitride precursors formed in situ by reaction of metal salts with a nitrogen source. Currently, template electrodeposition is the most commonly used method for producing uniform, high-density metal nanowires. Recent advances in the electrodeposition technique have made it possible to fabricate single crystalline nanowires from ferromagnetic, high melting temperature, metals Co, Fe and Ni and their alloys, with control over crystal structure and composition[7,8]. However the multistep technique is cumbersome and subject to surface roughening, high concentrations of stacking faults, fracturing of high aspect ratio structures, and contamination due to post-deposition template removal processes[9]. Whilst template-free self-assembly of single-crystal cobalt and nickel nanowires has been achieved, low yields and substrate limitations have limited applications of epitaxially-grown nanowires, while solvothermal growth methods typically produce aggregates of low aspect ratio nanowires[10,11]. To date, no general method of template-free self-assembly of binary or ternary metal alloy nanowires has been reported. Here we report a versatile and scalable fabrication technique for single crystalline metal and metal alloy nanowires (eg. Co, Ni, NiCo, CoFe, and NiFe)[12]. The method employs reduction of metal nitride precursors formed in situ by reaction of metal salts with a nitrogen source. Nanowires may be grown using gas-phase, solution-phase or a combination of gas- and solution-phase precursors. We also examine the roles of the reactants and intermediate metal phases in the uniaxial growth mechanism. Thiol reduction of the metal nitrides to the metallic phase at 550-600?C results in nanowire growth. In this process, sulfur acts as a uniaxial structure-directing agent, passivating the surface of the growing nanowires and preventing radial growth. The robustness and versatility of the method is demonstrated by achieving nanowire growth from gas-phase, solution-phase or a combination of gas- and solution-phase precursors. The fabrication method is suited to large-area CVD on a wide range of solid substrates. Our method will allow new generation of metallic nanowires for applications in high-performance spin based electronics, diagnostics and therapeutics. [1] H. Wu, D.S. Kong, Z.C. Ruan, P.C. Hsu, S. Wang, Z.F. Yu, T.J. Carney, L.B. Hu, S.H. Fan, Y. Cui, Nature Nanotechnology 8 (2013) 421. [2] U. Yogeswaran, S.-M. Chen, Sensors 8 (2008) 290. [3] S.A. Wolf, D.D. Awschalom, R.A. Buhrman, J.M. Daughton, S. von Molnar, M.L. Roukes, A.Y. Chtchelkanova, D.M. Treger, Science 294 (2001) 1488. [4] Y. Imura, K. Tsujimoto, C. Morita, T. Kawai, Langmuir 30 (2014) 5026. [5] F. Garcia-Sanchez, H. Szambolics, A.P. Mihai, L. Vila, A. Marty, J.P. Attane, J.C. Toussaint, L.D. Buda-Prejbeanu, Physical Review B 81 (2010) 134408. [6] R. Skomski, H. Zeng, M. Zheng, D.J. Sellmyer, Physical Review B 62 (2000) 3900. [7] H. Pan, B.H. Liu, J.B. Yi, C. Poh, S. Lim, J. Ding, Y.P. Feng, C.H.A. Huan, J.Y. Lin, J. Phys. Chem. B 109 (2005) 3094. [8] R.M. Metzger, V.V. Konovalov, M. Sun, T. Xu, G. Zangari, B. Xu, M. Benakli, W.D. Doyle, Ieee Transactions on Magnetics 36 (2000) 30. [9] G. Cao, D. Liu, Advances in Colloid and Interface Science 136 (2008) 45. [10] S.-i. Kim, H. Yoon, H. Lee, S. Lee, Y. Jo, S. Lee, J. Choo, B. Kim, Journal of Materials Chemistry C 3 (2015) 100. [11] Y. Soumare, C. Garcia, T. Maurer, G. Chaboussant, F. Ott, F. Fievet, J.Y. Piquemal, G. Viau, Adv. Funct. Mater. 19 (2009) 1971. [12] J. Scott, D. Totonjian, A. Martin, T.T. Tran, J. Fang, M. Toth, A. McDonagh, I. Aharonovich, C. Lobo, Nanoscale (2016).

Authors : Suhee Kang,* Rajendra C. Pawar, Caroline Sunyong Lee
Affiliations : Department of Materials Engineering, Hanyang University

Resume : Titanium dioxide (TiO2) is the cheapest with non-toxicity and higher stability. However, it suffers through poor absorption in visible irradiation due to large band gap energy of ~ 3.2 eV and high rate of recombination. To overcome these drawbacks, studies on adding doping materials or synthesizing with low band gap semiconductor materials, have been reported in the past. Hence, one of promising materials, non-metallic g-C3N4, is considered because of its band gap energy of 2.6 eV as well as its thermal and chemical stability. Moreover, the existence of g-C3N4 in visible region due to its strong covalent bonding of carbon and nitrogen atoms, has been confirmed. Additionally, it has been reported that TiO2/g-C3N4 composite showed stable state and good photoelectrochemical properties. In the present work, we tried to explore polymeric graphitic carbon nitride (g-C3N4) coating onto branched TiO2 nanorods via thermal method. Initially, aligned TiO2 nanorods were grown on to FTO (Fluorine-doped tin oxide) substrate with simple hydrothermal method at 150 °C/3h. After that, grown TiO2 film was treated with TiCl3 to make branched structures. After this, g-C3N4 layer was directly coated onto branched TiO2 structure using sintering process at 520 °C/4h in air atmosphere to increase its performance. TiO2/g-C3N4 films were analyzed via different analytical techniques to observe its improvement in absorbance and reduction in recombination losses. Based on photocatalysis measurements, it was seen that TiO2/g-C3N4 films show better performance than that of pristine. The enhanced performance was aroused form minimum recombination and strong absorbance after coating g-C3N4 onto TiO2 films. Furthermore, improvement in recombination losses were confirmed according to room temperature photoluminescence and electrochemical analysis. Finally, TiO2/g-C3N4 films showed excellent photocatalytic activities and hence could be used in water purification device technology.

Authors : Aadesh P. Singh,* Bodh Raj Mehta
Affiliations : Thin Film Laboratory, Physics Department, Indian Institute of Technology, New Delhi, India

Resume : This paper will present how RF-magnetron sputtering processed nanostructured thin films of metal oxides such as hematite (α-Fe2O3), titanium dioxide (TiO2) and bismuth vanadate (BiVO4) with tailored properties by hydrogen doping open up new vista of material properties, which can be transformed into advanced material technologies for solar water splitting. The effect of surface disordering by hydrogen doping in metal oxide thin films on optical, electrical and photoelectrochemical will be discussed. Herein, we demonstrate the effect of a partially reduction via hydrogen plasma treatment on metal oxide thin films as a simple and effective strategy to significantly improve the band edge positions and photoelectrochemical performance. Partially reduced hematite (Fe3O4:α-Fe2O3) by hydrogen treatment showed higher absorption cross-section under one Sun illumination and were found to be promising photoelectrode material with lower values of over-potential required to decompose water (in 1M NaOH). This was verified by substantially enhanced photocurrent densities (3.5 mA/cm2 at 1.0V/RHE) and reduced photocurrent onset potentials (from 0.87 to 0.55 V/RHE) in Fe3O4:α-Fe2O3 films, when compared to untreated hematite films. Hydrogen plasma treatment under non-equilibrium conditions did not alter the phase-structure but induced a valence dynamics among Fe-centers in the sub-surface region that was sustained by the incorporation of hydrogen in the hematite lattice.

Hybrid Materials for Functional Applications : Ion Tiginyanu
Authors : Dr. Cenk Aktas,* Oleksandr Polonsky, Thomas Strunskus, Michael Veith, Franz Faupel
Affiliations : Multicomponent Materials, Institute for Materials Science, Kiel University, Kaiserstr. 2, D-24143 Kiel, Germany; Saarland University, Medical Faculty-Homburg-Germany

Resume : Bi-phasic solid state composites of the type metal/metal oxide or element/element oxide can be synthesized in a single step method so called molecular "single source precursor" approach. Due to their singular genesis these nano scale composites show novel hetero-structures based on core-shell hierarchies (such as superlattices and composite nanospheres, nanorods or nanowires). They exhibit superior or new functional properties compared to their individual constituent compounds. In the current work, we review in particular the synthetical and mechanistical approach of bi-phasic (Al/Al2O3) nanostructures such as nanospheres, nanowires and nanoloops using a single source precursor. The impact of different synthetical conditions as well as of modification of surfaces by different methods including wet chemistry, vapor deposition and laser treatment and their technological relevance are presented briefly. Additionally, functional applications of the prepared surfaces are explained with some outstanding case studies. These case studies are primarily concerned with their use as biomaterials and their application in medicine as well as with their use as thin films for optics and functional surfaces. Chemical Society Reviews, 41, 2012, 5117-5130; 2. Small, 9, 2013, 1042-1046; 3. Journal of Biomedical Nanotechnology, 10, 2014, 831-845; 4. Nanotechnology, 25, 2014, 495101.

Authors : V. Postica, M. Hoppe,* D. Smazna, J. Gröttrup, R. Adelung, O. Lupan, N. Ababii, V. Sontea, Y. K. Mishra
Affiliations : Functional Nanomaterials, Institute for Materials Science, Kiel University, Kaiserstr. 2, D-24143, Kiel, Germany; Department of Microelectronics and Semiconductors Devices, Technical University of Moldova, 168 Stefan cel Mare Av., MD-2004 Chisinau, Republic of Moldova

Resume : In the semiconducting oxide family, zinc oxide is a very fascinating material with an extraordinary variety of morphologies and its tetrapodal (T) shapes and other nano-micro-crystals have received considerable attention. Recently we demonstrated a novel method as strategies for ZnO:Sn nano-micro-crystals (synthesized from chemical solutions SCS) and Sn- alloyed ZnO tetrapods (grown by flame transport synthesis FTS). In the case of FTS doping and alloying with Sn metal microparticles, the formation of a second crystal phase of Zn2SnO4 was observed resulting in multiple heterojunctions which is quite promising for UV detection and gas sensing applications. On the other hand, our group developed the cost-efficient method of doped ZnO nano-micro-crystallite films synthesis by SCS at low temperatures (< 90 ºC). In this study, the UV detection performances of the ZnO:Sn nano-micro-crystallite films films and ZnO-T alloyed with Sn-oxide (ZnO-T- Zn2SnO4) were compared in order to reveal the effect of morphology, as well as the most effective type of crystal structures for fast and highly selective detection of UV light (λ = 365 nm) and gasses. The ZnO: Sn nanostructured films by SCS demonstrated a quite good UV response (≈ 125), while ZnO-T-Zn2SnO4 networks showed a higher one (≈ 609), revealing the superiority of the tetrapod networks. ZnO-T-Zn2SnO4 networks also demonstrated a much faster response time. The fabrication strategies for nanosensors based on different types of hybrid nano- and microstructured ZnO materials will demonstrated here and corresponding photoelectrical studies including device sensing performances will be discussed in detail.

Authors : Mustafa Erkovan,* Erdem ?ennik, ?eyma Ürdem, Necmettin K?l?nç
Affiliations : Sakarya University, Department of Nanoscience and Nanoengineering, Sakarya, 54187, Gebze Technical University, Department of Physics, Kocaeli, 41400, Turkey; Sakarya University, Department of Nanoscience and Nanoengineering, Sakarya, 54187, Nigde University, Nanotechnology Application and Research Center, 51245 Nigde, Turkey; Nigde University, Mechatronics Engineering Department, 51245 Nigde, Turkey

Resume : Hydrogen is a renewable energy source and has many applications such as chemical production, fuel cell technology, fuel for cars, rocket engines, etc.. The detection of H2 in a wide range concentration is crucial for leak detection, safety issue and real time quantitative analysis. So, it requires hydrogen sensors that are accurate, fast and working in a wide hydrogen concentration. Various types of H2 sensors have been extensively studied depending on physico-chemical detection mechanism such as catalytic, electrochemical, resistor based, work function based, mechanical, optical and acoustic. In general, palladium (Pd) and Pd alloys are used as sensitive materials for metallic resistor type hydrogen sensor and there are several studies in literature. But there are a limited numbers of researches on hydrogen sensing properties of Pt. This work presents hydrogen (H2) sensing properties of platinum (Pt) and PtAg alloy thin films deposited on glass substrate by sputter technique with different thickness. The samples were characterized by XRD, SEM and (XPS) techniques for structural and chemical analysis. The XRD and XPS results for the Pt thin films are displayed a face-centered cubic crystalline structure. The obtained thin film contain no impurity peaks from both XRD and XPS, which is due to the high purity crystals. As the XPS spectrum of Pt from pure Pt films and PtAg films were compared, the relative shift was observed from PtAg alloy films. H2 sensing properties of Pt thin films were investigated at a temperature range from 30 °C to 200 °C. Temperature dependent resistances and the gas measurements of the Pt and PtAg alloy thin films were investigated under a dry air flow at a temperature range from 30 °C to 200 °C. The resistances of Pt thin films were linearly increased due to the their metalic structure. The H2 sensing properties of Platinum sensors were examined in the concentration range of 0.1 % - 1 % H2.It is directly proportional with temperature, and inversely proportional with the thickness of Pt thin film. The H2 gas sensing measurement results revealed that the 2 nm Pt thin film sensor is the best sensing performance to H2 at 30 °C. The sensitivity decreased at high temperatures but the best response time was obtained at high temperature with clear response-recovery, good stability. The results showed that Pt thin film sensor could be potentially used for H2 leak detection. The resistive hydrogen properties of PtAg alloy films study is going on and we will compare results from both Pt and PtAg alloys films. We think that Pt based thin film sensors and could be potentially used for H2 leak detection. This study was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) with project number of 114M853.

Authors : Yoshimi Iwasa,* Weifang Lu, Fumiharu Teramae, Satoshi Kamiyama, Haiyan Ou, Tetsuya Takeuchi, Motoaki Iwaya, Isamu Akasaki
Affiliations : Department of Materials Science and Engineering, Meijo University, 1-501 Shiogamaguchi, Tenpaku-ku, Nagoya 468-8502, Japan; Yoshimi Iwasa, Satoshi Kamiyama, Tetsuya Takeuchi, Motoaki Iwaya, Isamu Akasaki. Department of Photonics Engineering, Technical University of Denmark, DK-2800, Lyngby, Denmark; Weifang Lu, Haiyan Ou. ELSEED Corp., Innovative Science and Technology Building 2F, Meijo University, 2-1522 Shiiogamaguchi, Tenpaku-ku, Nagoya 468-0073, Japan; Fumiharu Teramae.

Resume : White LEDs with high color rendering index (CRI) are greatly demanded in general lighting applications. However, current major white LEDs composed of blue LED and yellow phosphor still have insufficient CRI, because of the lack of green and red color components. In this study, we present a new solid state phosphor material, porous SiC, which contains donor and acceptor impurities to create donor-acceptor-pair (DAP) recombination. Since this material can emit continuous visible spectrum similar to sun light, it is possible to fabricate high quality white LEDs with high CRI. Recently, we confirmed that DAP emission is enhanced and the peak wavelength is shifted to green-blue side due to the quantum size effect in porous SiC from a commercial n-type 6H-SiC substrate containing N (donor) and B (acceptor). In addition, it was reported that a non-radiative surface recombination was inhibited by specific surface passivation on porous SiC, while it has wider surface with problematic non-radiative surface recombination [1]. However, emission efficiency of such porous SiC is still low because of low B concentration of approximately 1x10^17 cm-3. In this study, we investigate an impact of doping concentrations of N and B on emission efficiency of porous SiC. As a method fabricating porous SiC, SiC samples are etched by anodic oxidation technique with a hydrofluoric acid solution. Moreover, as a passivation technique, Al2O3 deposited by atomic layer deposition (ALD) technique and annealed at a low temperature. The porous SiC after Al2O3 passivation has a broad blue-green light PL emission with a peak wavelength of 507nm, and the full width half maximum (FWHM) of 138.6nm. Compared with the porous SiC from commercial n-type substrate, the sample produced from intentionally codoped SiC has 2.63 times larger PL intensity. The result may show that the porous SiC with a combination of the bulk N and B codoped SiC is a promising candidate to generate high quality white light with a high CRI. References [1] Weifang Lu, et al. ?Photoluminescence enhancement in porous SiC passivated by atomic layer deposited Al2O3? CLEO 6-192 (2016).

Authors : Anil S. Gaikwad,* Swati A. Gupta, Yogesh S. Mhaisagar and Ashok M. Mahajan
Affiliations : Materials and Devices Laboratory for Nanoelectronics Department of Electronics, North Maharashtra University, Jalgaon India.

Resume : Porous low-k films are used as inter metal dielectric for wiring structure in nanoelectronic devices to reduce the interconnect delay, crosstalk noise and power consumption in ULSI circuits. Present work discusses the effect of porosity on different properties of low-k films. Porous low-k nanostructures were obtained by sol-gel spin coating method. Three solutions were prepared named as Sol A, Sol B and Sol C by using tetraethyl orthosilicate as a source of Si with solvent ethanol, DI water and HF as acid catalyst in different volumetric proportions. Sol A used to obtain xerogel films while Sol B used to obtained aerogel films followed by aging in solvent and supercritical drying. In Sol C porogen was added and is removed by annealing the samples to obtain the porous low-k films. Deposition of SiO2 and incorporation of Si-F, C-C low polar bonds is confirmed from the FTIR spectra. The porous structure of low-k films were investigated by using FE-SEM and AFM characterizations. The measured porosity was observed to be 71.64%, 58.5% and 34% for silica aerogel, porogen based porous low-k and xerogel films, respectively. The calculated dielectric constant from CV measurements of fabricated MIS structures observed to be decreased from 2.2 (xerogel) to 1.73 (aerogel).

Zinc Oxide Nanostructures: Fabrications and Advanced Applications : Yogendra Mishra
Authors : Prof. Dr. Junyi Zhai
Affiliations : Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences Beijing, China

Resume : Multifunctional micro/nano devices and systems are of important applications in smart electronics for health care, human-machine interfacing, infrastructure monitoring and security. In recent years, piezophototronic effect is developed fast since it offers a new method to improve/tune the optoelectronic properties dramatically. The key characteristic of the piezo-phototronic effect is that the carrier generation, transport, separation and/or recombination at the heterojunction/interface can be tuned by modulating the piezopotential which created and further tuned by externally applied strain. Therefore, one method to enhance piezo-phototronic effect is increasing piezoelectric charge at the interface. Another method to improve piezo-phototronic effect is reducing charge carrier recombination probability, the design of semiconductor composites heterojunction/interface should take into account their band positions and band gap. By interface engineering the p-n junction, piezo-phototronic effect can be improved. Piezophototronic effect can enhance the sensitivity of photodetector dramatically. Here, we show a self-powered GaN flexible film-based metal-semiconductor-metal (MSM) UV photoswitch. The asymmetric MSM structure was designed to suppress carrier recombination and enhance carrier transport. At self-powered condition (no external bias voltage), its UV on/off ratio reaches up to 4.67*105 with high reliability of on/off switching response. Also its UV detection shows an excellent sensitivity (1.78*1012 cmHz0.5W-1). In particular, strain modulation can improve the UV on/off ratio (~154%) by piezo-phototronic effect. When combine piezophototronics effect with magnetostriction, multi-field couplings can be realized. For example, magneto-optics and electro-optics, magneto-electrics and magneto-mechanics, piezotronics and piezophototronics, which could be of interest for fabricating functional devices in the fields of energy conversion, magnetic/optical imaging, high-density optical communication and information storage, smart sensing, and so on. Besides photoelectric conversion and electroluminescence, photoluminescence can be tuned by piezoelectric charge as well. Here have developed a new method of pressure sensing by using pressure/strain induced piezoelectric charge to tune PL intensity of InGaN/GaN MQW under small strain (0~0.15 %). Such modulation effect is distinct, linear and ultrafast. Based upon it, an all optical pressure sensor array by the piezo-phototronics effect has been developed to measure dynamic pressure distribution without the need of electricity. Beyond the limitations of electrical connection, our all-optical device offers a novel and suitable way for large-area, high-uniform, high resolution, ultrahigh speed pressure/strain distribution sensing.

Authors : Rabab Bekkari,* Boujemaâ Jaber, ,Damien Boyer, and Larbi laânab
Affiliations : LCS, Faculty of Sciences. Mohammed V University, Rabat, Morocco; CNRST, Angle Allal El Fassi / FAR, B.P. 8027, Hay Riyad 10000 Rabat, Morocco; Chemistry Institute of Clermont-Ferrand, Aubiere, France.

Resume : In this work, the photoluminescence properties of ZnO nanoparticles with various synthesis temperatures and concentrations were investigated. The photoluminescence spectra exhibit two types of emission: one is an ultraviolet UVemission centered at approximately 380 nm; and the other is a visible deep- level emission with a peak in range of 450-650 nm. The UV emission band is related to a near band-edge transition of ZnO, namely, the recombination of the free excitons , while the visible deep- level emissions band has previously been attributed to several defects in the crystal structure such as O-vacancy (VO), Zn-vacancy (VZn) , O-interstitial (Oi), Zn-interstitial (Zni), and extrinsic impurities. We show in this work that the emission energy and the intensity of the PL peaks depends remarkably not only the size but also the morphology of the elaborated nano-objects. The defects responsible for luminescence in the visible have also been identified and discussed.

Authors : Jorit Gröttrup, Daria Smazna, Iris Hölken, Fabian Schütt, Sindu Sree, Oleg Lupan, Sören Kaps, Rainer Adelung, Yogendra Kumar Mishra*
Affiliations : Functional Nanomaterials, Institute for Materials Science, Kiel University, Kaiserstr. 2, D-24143, Kiel, Germany

Resume : Nanoscale structures from inorganic materials such as metal oxides, with complex geometries, like tetrapods, multipodes, etc. have got much more research interest because of their huge significance in technological applications. Here the potential of the recently introduced flame transport synthesis (FTS) approach will be demonstrated which offers simple and cost-effective fabrication of different types of nano- and microstructures including tetrapods from zinc oxide (ZnO) which can be freely utilized for various applications. Due to 3D spatial geometry, the ZnO tetrapods find interesting applications as advanced linkers for joining the unjoinable polymers or smart fillers to fabricate self-reporting polymer composites. If these ZnO tetrapods are agglomerated, their spatially distributed arms prohibit the close packing and this feature could be extended to build a highly porous and mechanically flexible material of macroscopic expansions in form of interconnected network. Such type of interconnected ZnO networks find lot of technological potentials, for example UV photodetection, gas sensing, and photocatalysis. These porous networks have got further scope as a sacrificial 3D templates for fabricating new class of 3D nanoarchitectured hybrid 3D materials.


Symposium organizers
Arul. MURUGANSchool of Biotechnology, Royal Institute of Technology (KTH)

Roslackstullsbacken 15, Alvanova University Centre, Stockholm, SE-10639, Sweden
Jani KOTAKOSKIFaculty of Physics, University of Vienna

Boltzmanngasse 5, 1090 Vienna, Austria
Jost ADAMNanoSYD, Mads Clausen Institute

University of Southern Denmark, Alsion 2, DK-6400 Sonderborg, Denmark
Yogendra MISHRAUniversity of Kiel

Institute for Materials Science, Kaiser Str. 2, 24143 Kiel, Germany