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2019 Spring Meeting



Dielectric nanocomposites for energy, environment and health: from fundamental to devices

The intent of this symposium is to provide a unique exchange platform for interdisciplinary interactions on dielectric nanocomposites, from synthesis to device, connected to energy, environment and health. This includes semiconductor, metallic and polymeric nanoparticles and nanofillers embedded within oxide and non-oxide as well as polymeric matrices.


The possibility to incorporate sub-micron structures or fillers into a host matrix allows designing and creating nanocomposite materials with new physical properties, novel behaviors and improved physical, chemical and mechanical properties. As this research field requires a large range of skills ranging from chemistry, to physics, from material science to polymer science and biology, the symposium has the ambition to be a cross-road for researchers interested in new frontiers in dielectric nanocomposite systems connected to energy, environment and health.

In particular, the research topics discussed within the symposium will include nano-electronics and transport properties, nano-photonics and plasmonics, biosensing, energy harvesting, sensors, and additive manufacturing.

During each session, experimental and theoretical approaches as well as advanced characterization techniques will be combined in order to present the state of the art developments and strategies to fabricate and to improve the performance as well as potential applications of dielectric nanocomposites.

Hot topics to be covered by the symposium:

  • Synthesis of nanoparticles in dielectric matrices, e.g. oxide and non-oxide ceramics and polymers;
  • Optical properties: emission, absorption, scattering, luminescence, waveguiding, light confinement, plasmonics, plasmoelectronics;
  • Electronic properties: injection, transport, charge trapping, capacitance, memristance, photocurrent, electroluminescence, single electron effects;
  • Biomedical and sensing applications;
  • Bio-based additive manufacturing;
  • Modeling of precipitation, transport, quantum confinement, doping, electronic structure;
  • Devices: LEDs, optical amplifiers, waveguides, memristors, biosensors;
  • Advanced techniques for structural and chemical characterization at the nano- and sub-nanoscale, e.g. (S)TEM, advanced spectroscopies, synchrotron techniques, APT techniques.

Confirmed list of invited speakers:

  • Caroline Bonafos, CEMES (France)
  • Vincenzo Giannini, Imperial College (UK)
  • Jennifer Dionne, Stanford University (USA)
  • Tom Gregorkiewicz, University of Amsterdam (The Netherlands)
  • Christophe Delerue, Université de Lille (France)
  • Jean-François Dayen, Université de Strasbourg, (France)
  • Pietro Gucciardi, Università di Messina (Italy)
  • Carita Kvarnström, University of Turku (Finland)
  • Ignazio Roppolo, Politecnico di Torino (Italy)

Confirmed list of scientific committee members:

  • Riccardo Sapienza, Imperial College (UK)
  • Jan Linnros, KTH Royal Institute of Technolog (Sweden)
  • Fabrice Gourbilleau, CIMAP (France)
  • Antonio Terrasi, University of Catania (Italy)
  • Hervé Rinnert, Institut Jean Lamour (France)
  • Rosalía Serna, Instituto de Óptica (Spain)
  • Abdallah Slablab, Saarbrucken (Germany)
  • Marco Sangermano, Politecnico di Torino (Italy)


Selected papers will be published in the journal "Physica Status Solidi" (PSS) - Wiley.

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10:30 Welcome    
Inorganic Materials : Giancarlo Rizza
Authors : properties C. Bonafos1, M. Bayle2, P. Benzo1, A. Pugliara1,3,4, K. Makasheva3, G. Benassayag1, B. Pécassou1, E. Navarro5 and R. Carles1
Affiliations : 1 CEMES-CNRS, Université de Toulouse, 29 rue Jeanne Marvig, BP 94347, F-31055 Toulouse, France 2 Institut des Matériaux Jean Rouxel, UMR 6502 CNRS/Université de Nantes 2, rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3, France 3 LAPLACE, Université de Toulouse, CNRS, UPS, INPT, 118 route de Narbonne, F-31062 Toulouse, France 4 now at UMS 3623 - Centre de Micro-Caractérisation Raimond Castaing, 3 rue Caroline Aigle, 31400 Toulouse, France 5 IPE (Instituto Pirenaico de Ecología)-CSIC, Avda. Montañana 1005, Zaragoza 50059, Spain

Resume : Localized surface plasmon resonance (LSPR) of noble metal nanoparticles is widely exploited in plasmon-enhanced optical spectroscopy, photothermal therapy, photovoltaics or photocatalysis. In the visible range, silver nanoparticles (AgNPs) are the most efficient for electromagnetic field enhancement. AgNPs are multi-functionnal nano-objects that can be used as efficient plasmonic antenna, electron reservoirs for charge transfer or ion reservoirs with strong biocide activity. Recently, a strategy to design and produce hybrid metallic-dielectric substrates for optical spectroscopy and imaging has been proposed. By using low energy ion beam synthesis by implanting through micrometric masks, different architectures consisting of tri-dimensional patterns of AgNPs embedded in dielectric layers are conceived to simultaneously exploit the LSPR and optical interference phenomena. The twofold role of a single plane of AgNPs as embedded plasmonic enhancer and as charge carrier reservoir has been tested on few-layer graphene (FLG) located in dedicated areas at a controlled nm distance from the AgNPs. Electronic Raman scattering is shown as notably efficient to analyze the plasmon-assisted transfer of charge carriers between the two sub-systems (AgNPs and FLG). We will also show that these embedded AgNPs provide an efficient biocide activity when submersed in water and that the Ag+ ion release can be simply controlled by the distance of the AgNPs to the free surface.

Authors : G. Torrisi, E. Cavaliere, F. Banfi, G. Benetti, R. Raciti, L. Gavioli, A. Terrasi
Affiliations : University of Catania and CNR IMM ; Interdisciplinary Laboratories for Advanced Materials Physics (i-LAMP) and Università Cattolica del Sacro Cuore; FemtoNanoOptics group, Universit? de Lyon, Institut Lumière Matière (iLM), Université Lyon 1 and CNRS; Interdisciplinary Laboratories for Advanced Materials Physics (i-LAMP) and Università Cattolica del Sacro Cuore; STMicroelectronics, Stradale Primosole 50, 95100 Catania, Italy; Interdisciplinary Laboratories for Advanced Materials Physics (i-LAMP) and Università Cattolica del Sacro Cuore; University of Catania and CNR IMM;

Resume : The increasing interest in thin flexible devices has led to a strong demand for mechanically robust and electrically reliable transparent electrodes. Indium doped Tin Oxide (ITO) and Aluminum doped Zinc Oxide (AZO) are among the most employed transparent conductive oxides (TCO) and their reliability on flexible substrates have thus received a great attention. Recently, we developed a multi-layer TCO/Ag/TCO approach to respond to the present challenges, but a further enhancement of the flexibility seems to be achievable by replacing the continuous metallic intra-layer film with interconnected Ag nanoparticles (NP). To this aim, TCO/Ag NPs/TCO films were grown on glass and plastic (PEN) substrates: TCO were deposited by sputtering technique, while the Ag NP film were obtained by Supersonic Cluster Beam Deposition (SCBD). This technique generates a highly collimated beam of neutral metallic NPs at room temperature which maintain their morphology once deposited on a susbtrate. Here we show that a TCO/Ag Nps/TCO multilayer has superior flexibility, electrical stability and optical transmittance as compared to pure AZO, ITO and TCO/Ag/TCO films. The changes in the electrical resistance after mechanical bending as a function of the radius and number of bendings show a lower degradation of the electrical properties for the TCO/Ag Nps/TCO with respect to single TCO films or TCO/Ag/TCO where Ag is a planar continuous film of equivalent thickness deposited by sputtering. A finite element simulation of the bending process to calculate the stress distribution and intensity in the systems, shows a reduction of the stress at the Ag NPs intralayer.

Authors : Aida Naghilou [1], Ana Subotic [1], Ruth Lahoz [2], Markus Kitzler [3], Oscar Bomati Miguel [1,4], Wolfgang Kautek [1]
Affiliations : [1] University of Vienna, Department of Physical Chemistry, Vienna, Austria; [2] University of Zaragoza ? CSIC, Centro de Quimica y Materiales de Aragon, Zaragoza, Spain; [3] Photonics Institute, Vienna University of Technology, Vienna, Austria; [4] Universidad de Cadiz, Departamento de Fisica de la Materia Condesada, Cadiz, Spain;

Resume : Breast cancer (BC) is one of the most frequently diagnosed cancers among women. In modern medicine, various types of diagnostic imaging techniques have been developed and explored. Contrast enhanced digital mammography and magnetic resonance imaging in combination with X-ray film mammography in BC screening are complementary. However, widespread use of this multimodal approach requires the development of multimodal imaging contrast agents (MCAs) capable of responding efficiently to both X-ray radiation and magnetic fields. Through progress in nanoscience, it is possible to create a new class of MCAs consisting of colloidal nanoparticles (NPs)[1]. A promising technique for the generation of NPs is liquid-assisted pulsed laser ablation [2]. This technique is simple, environmentally friendly, and single step and combined with deionized water enables biological and medical applications. In this study, novel ceramic samples combining a magnetic iron oxide and an oxide phase of a radiopaque metallic element with high atomic weight (tungsten, tantalum, and bismuth) are produced. NPs generated from these targets by laser ablation in water and ethanol are studied. The characterization of the targets and the NPs focuses on the morphology, composition, and the crystallinity. [1] C. Núñez, S.V. Estévez, M. del Pilar Chantada, Journal of Biological Inorganic Chemistry, 23 (2018) 331-345. [2] D. Zhang, B. Gökce, S. Barcikowski, Chemical Reviews, 117 (2017) 3990-4103.

Authors : H.Kacem, Ah. Dhahri, E. Dhahri, J. Dhahri, K. Khirouni, K. Taibi.
Affiliations : Laboratoire de la Matière Condensée et des Nanosciences, Département de Physique, Faculté des Sciences de Monastir, Université de Monastir, 5019, Tunisia. - Faculté des Sciences, Monastir, Université de Monastir, Avenue de l'environnement, 5019, Monastir, Tunisia. - Laboratoire de Physique Appliquée, Faculté des Sciences de Sfax, BP 1171, Université de Sfax, 3000, Tunisia Laboratoire de Physique Appliquée, Faculté des Sciences de Sfax, BP 1171, Université de Sfax, 3000, Tunisia Laboratoire de la Matière Condensée et des Nanosciences, Département de Physique, Faculté des Sciences de Monastir, Université de Monastir, 5019, Tunisia. Laboratory of Physics of Materials and Nanomaterials Applied to the Environment, Faculty of Sciences of Gabes, University of Gabes, City Erriadh, 6079, Gabes, Tunisia. Laboratory of Materials Science and Engineering, Faculty of Mechanical Engineering and Process Engineering, University of Science and Technology Houari Boumediene, BP32 El Alia, Bab Ezzouar, 16111, Algiers, Algeria.

Resume : Lead free ceramic composition of Ca0.8Nd0.05K0.1Ti0.85Nb0.15O3, were synthesized by conventional solid-state sintering. The crystallographic structure was studied by X-ray diffraction experiments and Rietveld refinement revealed that our sample crystallizes in orthorhombic structure with Pbnm space group. The approximate grain size was found from experiment?s scanning electron microscopy. Using impedance spectroscopy technique, the dielectric and electrical properties were obtained from the conductance and capacitance measurements over a broad frequency range of 100 Hz-1 MHz and temperatures range of 570- 610 K. Nyquist plots showed that the dielectric response can be fitted by Cole-Cole model and represented by an equivalent circuit. Electric modulus formalism was employed to study the relaxation dynamics of charge carriers. The values of total conductivity for our sample were well fitting by the Jonscher?s universal law. Additionally, the dielectric measurements were confirmed by the photoluminescence spectra.

Authors : Y. Mansour, Y. Battie, A. En Naciri, N. Chaoui
Affiliations : LCP-A2MC, université de Lorraine

Resume : Gold nanoparticles (NPs) exhibits a surface plasmon resonance resulting from the collective oscillations of their conduction electrons. The resonant frequency is located in the visible range, which gives these plasmonic NPs unique optical properties. In particular, the position and amplitude of the plasmon resonance band may vary depending on their size, shape (aspect ratio) and the index of the host medium [1]. Their possible applications require pure samples and monodispersed distribution. The synthesis of the NPs by chemical techniques makes it possible to control the shape and the size of the NPs. However, it requires the use of stabilizing agents which lead to surface contamination by synthetic residues. This disadvantage could be limited by a physical technique ?laser ablation? in liquid medium [2]. However, this technique suffers from the lack of control over the shape and size of the produced NPs. The morphology of NPs generated by laser ablation in a liquid medium is correlated to the three essential steps of the process [3]: (i) Target/laser interaction. (ii) Mass transportation. (iii) Laser/NPs interaction suspended in the liquid - fragmentation. In order to understand the mechanisms governing each of these stages, it is necessary to study them separately. In this work, we focused on the interaction mechanisms between the laser beam and the NPs in suspension in the liquid (step 3). Depending on the energy absorbed by the NPs in suspension, they undergo fragmentation or reshaping. We investigated the mechanisms behind the fragmentation and the evolution of the shape distribution of NPs during laser exposure. We focused on the phase transformations of the NPs resulting from the absorption of the incident laser beam. Finally, we developed a model that allows establishing the phase diagram of NPs. This phase diagram is used to predict the final size and shape distributions of the NPs as a function of laser fluence. This model which takes into account the orientation of NPs with respect to the polarization of the laser beam, generalizes the one proposed by Takami [4] by considering nanorod shape. Systematic comparison between our modeling results about size and shape distributions and TEM images is given and analyzed. Références [1] A. Resano-Garcia, Y. Battie, A. En Naciri, S. Akil, N. Chaoui, J. Chem. Phys.142, 134108 (2015) [2] F.K. Mafune, J. Phys. Chem. B, 107, 12589 (2003). [3] B.G. Dongshi Zhang, Chem. Rev. 117, 3990 (2017). [4] A. Takami, J. Phys. Chem. B, 103, 2287(1999).

Authors : Saleh Chabok, Ali Reza Eivani
Affiliations : School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Iran

Resume : Degradable metallic biomaterials have recently found extensive applications in bone regeneration applications [1] and cardiovascular stents [2]. Magnesium and its alloys, e.g., WE43, are one of the promising candidates as they are biocompatible and can be degraded into the body with no or limited toxicity [3]. However, they suffer from high corrosion rate leading to a degradation rate and hydrogen evolution which cannot be accommodated by a human body [4]. Fabrication of composites may result in reduced corrosion rate and can be used as a solution for this problem.

12:30 Lunch    
Authors : Stefan Tappertzhofen, Giuliana Di Martino, Giorgio Divitini, Stephan Hofmann
Affiliations : Department of Engineering, University of Cambridge, Cambridge, United Kingdom; now with aixACCT Systems GmbH, Aachen, Germany; Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom

Resume : Memristive devices are building blocks for new memory and logic concepts, and can even emulate neuromorphic functions. Their ultra-fast and energy-efficient working principle is based on redox-reactions that allow for atomically scaled manipulation of conductive nanoparticles and filaments in an insulating host matrix. The electrochemical interactions of these particles with their ambient and the dynamics involved are still open questions, restricting significant device optimization. We report on the formation and dissolution of metal nanoparticles in silicon dioxide acting as a model host material system analyzed by transmission electron microscopy (TEM) and TEM tomography. Our study is complemented by applying a novel spectroscopic technique that allows for in situ and in operando characterization of the memristive effect by monitoring plasmonic resonances of the embedded nanoparticles and filaments. The optical signatures we detect suggest partial filament dissolution during device operation which is supported by our electron microscopy studies and statistical analysis of the switching properties. Our results indicate a complex and dynamic interplay between important electrochemical properties such as nucleation sites, redox rate, and defect concentration and velocity. We discuss the implication of these findings on the device performance and stability in general.

Authors : Etienne Talbot1, Rémi Demoulin1, Sebastien Duguay1, Philippe Pareige1, Dominique Muller2, Daniel Mathiot2
Affiliations : 1. Normandie Univ, UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, 76000 Rouen, France. 2. ICube Laboratory, Université de Strasbourg and CNRS, B.P. 20, 67037 Strasbourg Cedex, France

Resume : Materials consisting of silicon nanocrystals (Si-ncs) embedded in silicon dioxide (SiO2) are the subject of an intense research activity due to their numerous potential applications in the fields of optoelectronic and photonic. Moreover, Si-ncs can present a localized surface plasmon resonance but require substitutional doping using type p or n dopants. The efficiency of doped materials strongly depends on the dopant location in the host matrix. In this way, an accurate control of the dopant location is necessary in order to improve the quality of these systems. In this work, N-doped (Arsenic and Phosphorus) and undoped Si nanocrystals in silica using co-implantation synthesis have been investigated using Atom Probe Tomography. For each sample, the 3D spatial distribution of Si and dopant atoms has been obtained allowing to study the structure of these films at the atomic scale and to investigate the location of impurities and the Si clustering characteristics. These results evidence an influence of the dopants on the Si-ncs characteristics. Moreover, it has been shown that n-type impurities are efficiently introduced in Si-ncs. The effect of the dopant nature on the structural properties will be discussed.

Authors : Mota-Santiago P.1, Kremer F.2, Rizza G.3, Dufour C.4, Khomenkov V.4, Notthoff C.1, Hadley A.1, Kluth P.1
Affiliations : 1Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra ACT 2601, Australia 2Centre for Advance Microscopy, Australian National University, Canberra ACT 2601, Australia 3Ecole Polytechnique, Laboratoire des Solides Irradies (LSI) CEA/DSM/IRAMIS, CNRS 91128 Palaiseau Cedex, France 4CIMAP/CEA/CNRS/ENSICAEN/ Universite de Caen, 6 Boulevard du Marechal Juin, 1405 Caen Cedex 4, France

Resume : In this contribution we report on the study of the elongation process of spherical Au nanoparticles (NPs) in amorphous silicon nitride (a-Si3N4), silicon dioxide (a-SiO2) and at the interface of the two materials by swift heavy-ion irradiation (SHII). The process results in the formation of highly aligned embedded metal nano-rods. The samples consist of a two deposited a-Si3N4/a-SiO2 thin layers with a thin Au layer deposited via thermal evaporation in between. Rapid thermal annealing (RTA) at 950 °C in a N2 atmosphere was then used to induce the breakdown of the continuous Au film into a system of discrete Au NPs. The ion beam shaping process was promoted by SHII with 185 MeV Au ions at fluences ranging from 1.0?30.0×1013 cm-2 in normal incidence. Transmission electron microscopy (TEM) showed that after the RTA an array of Au NPs has been formed at the interface between the bottom and the top layer. The formed NPs size distribution is characterized by a mean particle size of ~25 nm. A lower elongation rate in a-Si3N4 was observed in comparison to a-SiO2 upon irradiation of Au NPs embedded in a single layer. A similar behaviour was observed at the interface between the two materials leading to a preferential elongation towards a-SiO2. The TEM data also demonstrate the presence of nanoporosity in the Au NPs when embedded in the a-Si3N4 layer or at the SiO2/Si3N4 interface. Numerical calculations based on the three-dimensional inelastic thermal spike model showed that the preferential elongation is the result of the higher thermal conductivity of a-Si3N4. However, the origin of the nanoporous NPs remains unclear.

Authors : Y. Zhang, A. Apostoluk, B. Masenelli, S. Daniele, N. Le Bail, C. Theron, T. Cornier
Affiliations : 1. Y. Zhang; A. Apostoluk; B. Masenelli Université de Lyon, Institut des Nanotechnologies de Lyon (INL, UMR CNRS 5270), Institut National des Sciences Appliquées de Lyon (INSA Lyon), France 2. S. Daniele; N. Le Bail; C. Theron; T. Cornier Université de Lyon, Institut de Recherches sur la Catalyse et l?Environnement de Lyon (IRCELYON, UMR CNRS 5256), Université Claude Bernard Lyon 1, France

Resume : ZnO can have excellent optical properties as a wide bandgap semiconductor with many types of intrinsic defects, such as O vacancy and Zn interstitial. The visible photoluminescence (PL) of ZnO originating from defects makes it a promising candidate for applications such as white light emitting diodes (WLEDs) and down-shifting layer for solar cells. The environmentally-friendly nature of ZnO is another driving force for the research in ZnO to replace rare-earth-based phosphors as WLEDs material. In our previous study, a hybrid sphere structure of ZnO nanoparticles and polyacrylic acid (PAA) matrix fabricated through a hydrolysis method has proven an efficient material emitting intensively in the visible range. [1] Herein, we present a general and in-depth study of the effect of dopants in ZnO hybrid structure. Various dopants are introduced into ZnO hybrid structure in order to optimize the photoluminescence of ZnO nanoparticles. Effects of dopant nature, size and valence are investigated at different doping concentrations. The emission color of doped ZnO nanoparticles can be tuned in a wide visible range between yellow and green and the photoluminescent quantum yield (PL QY) can be improved by specific doping. Reference [1] Zhu, Y., A. Apostoluk, P. Gautier, A. Valette, L. Omar, T. Cornier, J. M. Bluet, K. Masenelli-Varlot, S. Daniele, and B. Masenelli. Scientific reports 6 (2016): 23557.

Authors : Ahmad Hamdan
Affiliations : Groupe de physique des plasmas, Département de Physique, Université de Montréal, Montréal (Qc), H3C 3J7, Canada

Resume : Plasmas in- or in-contact with liquids have been extensively investigated due to their high potential for a wide range of applications including but not limited to, water treatment, material synthesis and functionalization, bio-medical applications, etc. In-liquid plasmas, produced by nanosecond electrical discharges, are classified as processes with high-yield of nanomaterial synthesis. In addition, plasma properties, in terms of electron density, temperature, and pressure, are very unique and very different from those of gas-phase plasmas. Because of the flexibility on the electrodes and on the liquid, a wide family of nanomaterial can be synthesized. In this paper, our purpose is to provide an overview of the process, by revealing the physics behind the in-liquid electrical discharges. Also, we will present our recent findings on the discharges at the interface of two liquids. Indeed, we successfully investigated the discharges in two immiscible liquids, having very different electrical permittivities (n-heptane-water and hexamethyldisilazane-water). We will show that a discontinuity in the dielectric permittivity could significantly enhance the yield of the process, that's the synthesis of carbon-based nanomaterials (n-heptane-water) or H:SiOC nanoparticles (hexamethyldisilazane-water). A full characterization of the synthesized material will be presented and discussed.

15:30 coffee break    
Magnetic Nanoparticles : Simona Boninelli
Authors : J. A. Silva (1), C. Gouveia (2), G. Dinis (2), H. Araújo (2), A. M. Pereira (1)
Affiliations : (1) IFIMUP and IN ? Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal; (2) EQS Global, Rua Joaquim Dias Rocha, n.º 354 Zona Industrial da Maia 1, sector X, 4470-211 Maia, Portugal

Resume : Regular inspection of petrochemical, nuclear and electrical power generation facilities is critical to ensure safety and avoid health and environmental issues. The periodic evaluation of the integrity of these infrastructures requires non-destructive evaluation (NDE) as well as equipment that can withstand demanding conditions (e.g. high temperatures, corrosive ground, etc) [1]. Magnetostrictive materials have become an important transduction tool to use in NDT of corrosion and defects in pipelines. FeCo is one of the most cost-efficient magnetostrictive materials, as it has a large magnetostrictive coefficient and is cheap compared with rare-earth based ferromagnets while offering competitive advantages over its piezoelectric and optical counterparts [2]. FeCo is usually fabricated in sheets and rods but is too brittle to be worked and applied in the field of monitoring. To overcome this issue, we report the fabrication of an FeCo-resin composite, which is processed by screen-printing. It is composed of FeCo nanoparticles prepared by a polyol method and a binding paste. The obtained thick films present magnetostriction as well as superior mechanical stability. Characterization results are presented, including morphological, atomic and magnetic techniques, such as SEM, XRD, and VSM. Magnetostriction measurements were performed and are compared with results from bulk FeCo. [1] Heo, T. et al. Nucl. Eng. Technol. 48, 1404?1411 (2016) [2] Turcu, F. O. (Università di Pisa, 2008)

Authors : L.-M. Lacroix1, C. Garnero1, B. Warot-Fonrose2, K. Soulantika1, C. Meny3, P. Fau4, G. Viau1, P. Poveda5, B. Chaudret1
Affiliations : 1. Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, Toulouse, France 2. CEMES-CNRS, Toulouse, France 3. IPCMS, Université de Strasbourg, Strasbourg, France 4. LCC, Toulouse, France 5. ST Microelectronics Tours, France

Resume : Soft magnetic nanoparticles (NPs) are promising candidates for a wide range of applications ranging from microelectronics to nanobiotechnology. Among them, FeCo alloy presents the highest saturation magnetization (Ms = 240 emu/g) combined with a low anisotropy constant (K = 1,5.104 J/m3). Single crystalline FeCo nanoparticles with tunable size and shape were prepared by an organometallic synthesis.1 The nature of the ligands introduced drastically affects the reactivity of the precursors and thus the chemical distribution within the nanoparticles. The presence of the B2 short-range order was evidenced in FeCo nanoparticles combining 57Fe Mössbauer, zero field 59Co Ferromagnetic Nuclear Resonance (FNR) and X-ray diffraction studies. The as-prepared nanoparticles exhibit magnetic properties comparable with the ones of the bulk (Ms = 226 Am².kg-1) and remarkable magnetotransport properties.2 Composite magnetic materials were prepared by controlled impregnation of these FeCo nanoparticles into mesoporous silicon3 or epoxy matrix.1 These led to a successful proof-of-concept of integration on inductor-based filters (27% enhancement of the inductance value at 100 MHz).

Authors : Valentina Piotto, Lucio Litti, Piero Riello, Moreno Meneghetti
Affiliations : University of Padova; University of Venezia

Resume : Within the nanobiotechnology field, magneto-plasmonic nanomaterials are very promising for applications like drug delivery and biological sensing. These nanostructures can be easily manipulated with a magnetic field, while Raman active molecules attached on the plasmonic surface can be detected even in low concentration thanks to the SERS effect. Here we present a magnetic core covered with a silica shell which is decorated with gold nanoparticles in a core-shell-satellite structure. In the perspective of a further functionalization with biological species to do cell targeting, gold surface needs to be as clean as possible. For this reason, laser ablation has been chosen as top-down synthesis to obtain nanoparticles avoiding the use of surfactants. Laser ablated magnetic nanoparticles are usually produced from an iron target to get magnetite nanoparticles in the range of 30-40 nm that are less easy to functionalize in a core-shell-satellite structure. Therefore, magnetic nanoparticles are synthetized up to 100-200 nm starting from a strontium ferrite magnet. A full characterization of the magnetic component and the final structures is presented. Magnetophoresis is studied to understand the motion of magnetic nanoparticles in liquid under the presence of a magnetic field gradient. Finally, very intense SERS signals of the final nanostructures reveal their potential in biological applications, whereas the strong absorption in the NIR suggests their use in photothermal therapy.

Authors : J. Macutkevic1, D. Meisak1, A. Plyushch1, V. Samulionis1, J. Banys1, P. Kuzhir2, V. Fierro3, A. Celzard3
Affiliations : 1- Faculty of Physics, Vilnius University, Sauletekio 9, Vilnius LT-10222, Lithuania; 2- Research Institute for Nuclear problems of Belarusian State University, Bobruiskaya Str., 11 Minsk 220030 Belarus; 3- IJL-UMR Universite de Lorraine-CNRS, ENTSIB, 27 Rue Philippe Seguin, BP 21042, Epinal Cedex 9.

Resume : Ferroelectric and ferromagnetic polymeric composites are very attractive in various applications due to the possibility make large area, flexible and cheap devices. Ferroic polymeric materials can be obtained by two different ways: by producing a ferroic polymer or by introducing ferroic particles into non ferroic polymer matrix. In this presentation the sinergy effects between ferroic and carbon nanoparticles were investigated in both systems. First, of all epoxy resin composites with triglycine sulfate (TGS) and graphite nanoplatelets (GNP) were fabricated and studied by means of broadband dielectric spectroscopy (20 Hz ? 3 GHz). The ferroelectric origin of the phase transitions was also confirmed by piezoelectric investigations. Although the phase transition temperature is independent of GNP concentration, the piezoelectric and dielectric properties of composites are strongly improved by GNP in a broad temperature range. This gives evidence for the strong synergy between GNP and ferroelectric particles. The synergy effect appears due to the better distribution of TGS particles in ternary composites and the creation of electric fields by GNP inside the composite. The synergy effects were also investigated in PVDF composites with different kind of nanoparticles. It was established that the addition of Fe nanoparticles have the significant impact on the electrical percolation and the microwave absorption of PVDF and carbon nanotubes composites.

Authors : Vaibhav Singh Bhugra, Mohsen Maddah, Grant Williams, Thomas Nann
Affiliations : Vaibhav Singh Bhugra - Victoria University of Wellington (School of Chemical and Physical Sciences); Mohsen Maddah - Victoria University of Wellington (School of Chemical and Physical Sciences); Grant Williams - Victoria University of Wellington (School of Chemical and Physical Sciences); Thomas Nann- University of Newcastle (School of Mathematical and Physical Sciences)

Resume : Magnetoelectric (M.E) effect is simply an induced magnetization of a material in an external electric field and vice versa. The magnetoelectric effect in two-phase composite materials is known to be higher as compared to the single phase M.E materials. The coupling in two-phase materials takes between the magnetostrictive and piezoelectric phases respectively. A high molecular ferroelectric compound diisopropylammonium bromide (DIPAB) was dispersed in poly-(vinylidene fluoride) (PVDF) matrix. The mixture was spun using the rotating drum electrospinning setup to produce very well aligned nanofibers of DIPAB-PVDF that have almost pure electroactive ?-phase along with preferred (001) orientation. The nanofibres with different weight % of DIPAB were characterized by infrared spectroscopy, X-Ray diffraction, scanning electron microscopy and transmission electron microscopy. The results indicated that DIPAB was homogenously dispersed in the form of in-situ grown nanoparticles within the PVDF nanofibres along with the enhancement of ?-phase of PVDF. This is the highly piezoelectric phase of our composite nanofibers. The crystallinity of the polymer is also enhanced with increasing DIPAB content in the nanofibers. The frequency dependent dielectric constant and dielectric loss were improved by almost 12 times with increasing DIPAB content in the nanofibers as compared to usual electrospun PVDF nanofibres. These nanofibers also exhibited higher ferroelectric properties because of ionic polarization by highly ferroelectric DIPAB, interfacial polarization at the interface of DIPAB and PVDF and orientation polarization. The monodispersed magnetite nanoparticles are synthesized by effective monomer growth method in organic media. To make them compatible with PVDF phase, ligand exchange is performed to enhance the stability of these nanoparticles in PVDF media. The magnetic SQUID measurements proves a high saturation magnetization in these nanoparticles. The addition of these nanoparticles to the DIPAB ? PVDF result to the formation morphologically controlled magnetoelectric nanofibers along with enhanced properties as mentioned earlier.

Poster session 1 : Giancarlo Rizza
Authors : Sandhya Susarla, Thierry Tsafack, Peter Samora Owuor, Anand B. Puthirath, Jordan A. Hachtel, Ganguli Babu, Amey Apte, BenMaan I. Jawdat, Martin S. Hilario, Albert Lerma, Hector A Calderon, Francisco C. Robles Hernandez, David W. Tam, Tong Li, Andrew R. Lupini, Juan Carlos Idrobo, Jun Lou, Bingqing Wei, Pengcheng Dai, Chandra Sekhar Tiwary, and Pulickel M. Ajayan
Affiliations : Sandhya Susarla; Thierry Tsafack; Peter Samora Owuor; Anand B. Puthirath; Ganguli Babu, Amey Apte, BenMaan I. Jawdat; Jun Lou; Chandra Sekhar Tiwary, and Pulickel M. Ajayan: Department of Materials Science and Nano-engineering, Rice University, Houston, TX, U.S.A, 77030 Jordan A. Hachtel; Juan Carlos Idrobo : Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA 37831 Martin S. Hilario: Air Force Research Laboratory, Kirtland Air Force Base, Albuquerque NM 87117 Albert Lerma: Leidos, Inc., Albuquerque, NM 87106 Francisco C. Robles Hernandez: The University of Houston, Mechanical Engineering Technology, Houston, TX, USA, 77204 Hector A Calderon: Instituto Politécnico Nacional, ESFM, UPALM, Zacatenco, Mexico, CDMX, Mexico, 07338 David W. Tam; Pengcheng Dai : Department of Physics and Astronomy, Rice University, U.S.A., 77030 Tong Li; Bingqing Wei : Department of Mechanical Engineering, University of Delaware, USA, 77030 Andrew R. Lupini: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA 37831 Chandra Sekhar Tiwary: Department of Materials Science and Engineering, Indian Institute of Technology, Gandhinagar, Palaj, Gandhinagar, Gujrat, India, 382355

Resume : Dielectric materials form important passive components in electronic circuits, insulation, shielding and wireless communications 1?6. Emerging flexible and conformable electronics that are stretchable and mechanically flexible 5,7?10 requires encapsulation with corresponding flexible and lightweight high dielectric constants (K) materials 11,12. Conventional dielectric materials are either ceramics or polymers 3,8,12?16. Ceramic dielectrics are high-K brittle materials with large losses and low breakdown voltage 3,13,14 whereas polymers have high dielectric strength and flexibility but low-K values limit their application in devices 8,12,14?16. To get the best of both polymer and ceramic dielectrics, polymer composites with various high-K ceramic nanoparticle fillers have been considered 17,18. Here, deviating from this composite approach we develop a new monolithic, light weight, flexible, high-K dielectric material by combining two common non-polar, brittle constituents, sulfur (S) and selenium (Se) through a simple scalable co-melting process. The S-Se semi-crystalline alloys made of non-metallic chalcogen atoms show viscoelastic behavior and soft polymer-like mechanical flexibility with a dielectric strength (40 kV/mm) and a high dielectric constant (K=74) comparable to some of conventional metal oxides. The individual components of the alloy, S and Se, have both low K and theoretical models suggest that the high dielectric constant in S-Se is the result of strong dipole moment generated due to the unique structural and electronic interactions between Sand Se. These chalcogen alloys could fill the gap for soft high-K dielectric materials in several flexible device applications.

Authors : Haena Yim, Ji-Won Choi
Affiliations : Center for Electronic Materials, Korea Institute of Science and Technology, Seongbuk-gu, Seoul 02792, Republic of Korea

Resume : Development of wearable and biomedical electronic applications demand advanced materials for electronic devices such as micro-sensor, capacitors, and thin-film field-effect transistors. With this aim, two-dimensional (2D) materials have been studied because of its high mobility and great optical properties. Among them, Dion-Jacobson phase nanosheets such as Sr2Nb3O10 are well known as efficient dielectrics because of its great dielectric properties even for thickness down to 20 nm. Also, it shows high transparency. Therefore, here, we demonstrate the transparent dielectric capacitors using A-site modified Sr2Nb3O10 (SANO) nanosheets with oxide/metal/oxide (OMO) multilayer conducting electrode. We deposited SANO multilayer thin film by Langmuir-Blodgett method and deposited th OMO electrode by sputtering system. The crystal and dielectric properties of OMO/SANO/OMO structured dielectric capacitor were investigated, and this capacitor shows great capacitance. Therefore, we expect that this transparent dielectric capacitor could be applied for next-generation transparent devices.

Authors : A. Bayart 1, S. Leroy 1, F. Szczepanski 1, J. F. Blach 1, J. Rousseau 1, A. Katelnikovas 2, S. Saitzek 1
Affiliations : 1 Univ. Artois, CNRS, Centrale Lille, ENSCL, Univ. Lille, UMR 8181 - UCCS - Unité de Catalyse et Chimie du Solide, F-62300 Lens, France ; 2 Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko 24, Vilnius, LT-03225, Lithuania

Resume : In the last decades, La2Ti2O7 oxides with a layered-perovskite structure were widely studied due to their multifunctionality. Indeed, these oxides can be used for their photo-catalytic properties in particular for the degradation of pollutants or for the production of hydrogen by water splitting. These oxides can be also utilized for their piezo-/ferro-electric properties with high Curie temperatures (Tc?1500 °C), for the design of piezoelectric systems (Micro-/Nano-ElectroMechanical Systems (M/NEMS) or piezoelectric injectors) that can operate in extreme environments, particularly for applications in the automotive or aerospace industry. In the present work, the La2Ti2O7 oxide has been used as a host matrix to develop novel phosphors with interesting luminescence properties and we present a study on the synthesis and the characterization of Eu3+ and Er3+ co-substituted lanthanum titanates (La2Ti2O7) with layered-perovskite structure. Structural and luminescence (emission and excitation spectra, lifetime, quantum yield) properties will be discussed in this work. We highlighted that the co-substituted oxide can present two types of emission as a function of the excitation wavelength. For an excitation in the UV domain, the oxide emits in the orange-red spectral range, while under a NIR excitation, green emission is observed that can be explained by an upconversion phenomenon. The effect of the substitution percentage and the temperature will be discussed in this work.

Authors : Hilal Balout, Nathalie Tarrat, Joel Puibasset, Simona Ispas, Fabrice Gourbilleau, Kremena Makasheva, Caroline Bonafos, Magali Benoit
Affiliations : CEMES, CNRS et Université Toulouse,Toulouse, France; CEMES, CNRS et Université Toulouse,Toulouse, France; ICMN, Université Orléans, Orléans, France; LCC, Université Montpellier, France; CEMES, CNRS et Université Toulouse,Toulouse, France; LAPLACE, Université Toulouse,Toulouse, France; CEMES, CNRS et Université Toulouse,Toulouse, France; CEMES, CNRS et Université Toulouse,Toulouse, France;

Resume : Silver nanoparticles (AgNP) are widely used in the health sector and in industry because of their exceptional antimicrobial activity. In a previous work [1], the toxic effect on photosynthesis of algae from small AgNPs (size < 20 nm) implanted in an amorphous silica layer has been demonstrated. This toxic effect is due to the release of Ag+ ions into the aqueous medium, which has been shown to be highly toxic depending on (i) the distance at which the AgNPs are buried below the silica free surface and (ii) the structural properties of the silica matrix. In order to finely adjust the release rate of Ag+ ions by these nanocomposites, it is necessary to determine which are the key factors limiting or promoting the ionic diffusion within the silica matrix. In the aim to better understand the mechanisms of Ag+ ion release, we first modelled by DFT the interface between amorphous silica and the densest crystalline facets of AgNPs (100), (110) and (111). The first results obtained show a significant structural reorganization at these interfaces accompanied by the appearance of defects in silica, these phenomena can constitute a first step in the mechanism of releasing silver ions into the target medium. [1] A. Pugliara et al., Science of the Total Environment 565, 863?871 (2016)

Authors : Mota-Santiago P.1, Kremer F.2, Rizza G.3, Dufour C.4, Khomenkov V.4, Notthoff C.1, Hadley A
Affiliations : 1Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra ACT 2601, Australia 2Centre for Advance Microscopy, Australian National University, Canberra ACT 2601, Australia 3Ecole Polytechnique, Laboratoire des Solides Irradies (LSI) CEA/DSM/IRAMIS, CNRS 91128 Palaiseau Cedex, France 4CIMAP/CEA/CNRS/ENSICAEN/ Universite de Caen, 6 Boulevard du Marechal Juin, 1405 Caen Cedex 4, France

Resume : The shape transformation of nearly spherical Au nanoparticles (NPs) when embedded in, and at the interface of, a-Si3N4 and a-SiO2 thin films was studied upon irradiation with 185 MeV Au ions at different fluences. The samples were characterized post irradiation using transmission electron microscopy and high angular annular dark field microscopy in scanning transmission electron microscopy mode. The results demonstrate that: (i) Au NPs do elongate when embedded in a-Si3N4, (ii) the process is less efficient in a-Si3N4 while the geometry of the elongated Au NPs resembles a rhombic-like geometry, (iii) when the Au NPs are located at the interface they shift or diffuse towards the a-SiO2 layer before ion-shaping occurs after which it happens predominantly towards the a-SiO2 layer. For this work, numerical calculations using the three-dimensional version of the inelastic thermal spike model were performed. We sought to achieve a better understanding of the time-evolution of the thermal profile around one Au NP while embedded in a-Si3N4, a-SiO2 or at the interface of the two materials. From the numerical simulations, clear differences in the thermal profile experienced by the Au NPs due to the specific combination of electron-phonon coupling strength and thermal conductivity in the two host materials are apparent. It was found that the higher thermal conductivity of a-Si3N4 results in a reduced thermal spike lifetime in comparison to a-SiO2, responsible for the reduced shaping efficiency in a-Si3N4 and asymmetric shaping at the interface.

Authors : Andriy V. Kityk, Piotr Pawlik, Anatoliy Andrushchak, Robert Wielgosz, Olha Kityk, Patrick Huber, Kathrin Sentker, Przemys?aw Kula, Wiktor Piecek, Petra Goering, Monika Lelonek
Affiliations : Czestochowa University of Technology, Czestochowa, Poland; Czestochowa University of Technology, Czestochowa, Poland; Lviv National Polytechnic University, Lviv, Ukraine; Energia Oze Sp. z o.o., Konopiska, Poland; Energia Oze Sp. z o.o., Konopiska, Poland; Hamburg University of Technology, Hamburg, Germany; Hamburg University of Technology, Hamburg, Germany; Military University of Technology, Warszawa, Poland; Military University of Technology, Warszawa, Poland; SmartMembranes GmbH, Halle, Germany SmartMembranes GmbH, Halle, Germany

Resume : Liquid crystals (LCs) embedded into tubular nanopores of anodized aluminium oxide (AAO) membranes form LC nanocomposites (AAOLCN) that exhibit macroscopic optical and dielectric anisotropy. Molecular ordering of nanoconfined LC phases results in macroscopic excess linear birefringence, that in most cases substantially dominates geometrical birefringence caused by the elongated pore geometry. In addition, confined chiral nematic and smectic LC phases exhibit circular birefringence (optical activity) due to long periodic helicoidal structures developed along the pore axis. These, in many cases spatially inhomogeneous molecular structures, strongly depend on the anchoring conditions defined by host-guest interactions at the pore wall. The pore surface can be modified by chemical treatment, such as e.g. silanization, or relevant polymer film coatings, that enhance normal or tangential molecular anchoring. Accordingly, optical anisotropy can be tailored in a wide range. Applying external electric or magnetic fields may also influences the molecular ordering inside the pores changing the anisotropy of AOLCN materials opening a prospective for their functional optical and optoelectronic applications. We report the molecular ordering of both nonchiral and chiral LCs embedded into parallel-arrays of cylindrical channels of AAO membranes of different pore diameters (20-75 nm). Linear and circular birefringence of AOLCN are measured simultaneously by a modulation polarimeter. Molecular ordering inside the nanopores is explored on both nonchiral nematics and cholesteric (chiral nematics) LCs and is compared with the bulk behaviour. Applying film coatings of polymers SE-130 or SE-1211 at the pore surface enhances tangential or normal anchoring, respectively. In a number of cases polymer treatment leads to strong modification of a confined molecular ordering resulting in the sign change of the optical birefringence and/or optical activity. This work is a part of a project that has received funding from the European Union?s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 778156.

Authors : Stepanova I.V., Petrova O.B., Kolobkova E.M., Zykova M.P., Avetissov I.Ch.
Affiliations : D.Mendeleev University of Chemical Technology of Russia

Resume : Materials containing Bi-centers, which are characterized by 500 nm absorption band, and 1300 nm luminescence broad band, are promising candidates for lasers and fiber-optic amplifiers. To date these Bi-centers are considered as nanoclusters with a complex structure which includes 2 or more components: neutral Bi atoms, Bi3 -Bi2 dimers combined with a vacancy, Bi , Bi5 ions, etc. The glasses in the Bi2O3 concentration range of 5-50 mol%, including additionally doped with Cr2O3 as an oxidizer have been synthesized at 1050-1100?C and cooling with various rates. Optical and spectral-luminescent properties of glasses were investigated. Bi-centers concentration increased linearly with the Bi2O3 content in Cr-less glasses. The decrease of synthesis temperature or cooling rate led to Bi-centers content decrease. The addition of just 0.01 mol% Cr2O3 into the glass led to complete destruction of Bi-centers due to the oxidation-reduction interaction between Cr- and Bi- ions. Glasses' heat treatment under various conditions was carried out. When treated in air a gradual discoloration of the samples was observed due to the oxygen diffusion into the glass. The original red color has been completely restored by re-sintering the clarified glass. All the processes of color change are described in terms of formation/destruction of optically active Bi-centers. This research was financially supported by the grant (10.4702.2017/BC).

Authors : Yokub Suvonovich Ergashov
Affiliations : Tashkent state technical university

Resume : One of the main problems of modern nanoelectronics is to obtain homogeneous silicon spatial quantum-dimensional structures on the surface of semiconductors and dielectric films. Of special significance is the phenomenon of self-organized formation of nanostructures (islands) - i.e. spontaneous formation of a large number of nanostructures due to the formation of the type ?matrix-adsorbed atom? system itself. Such structures can be obtained by deposition of atoms of various elements on the surface of special substrates. However, the size of these islands and the distance between them are random. By creating certain conditions, it is possible to obtain regularly spaced and equally sized nanostructures of high stability. In particular, such magic clusters were obtained in [1] on a reconstructed (7x7) surface of atomically pure Si (111) by sputtering ~ 0.3 aluminum monolayer at T = 550 ° C under ultrahigh vacuum conditions. Our preliminary studies showed [2] that such defects can be created by the technique of low-energy ion bombardment in combination with annealing. In this work the impact of Ca and Si nano-scale structures on parameters and density of states of single-crystalline CaF2 (111) was studied. It was shown that at low concentration of ions of Ar+ (D?5?1015 cm-2) one witnesses formation of nanoscale phases on CaF2 surface. It was revealed that these phases lead to narrowing of the forbidden band ?g between the phases by 4-4,5 eV. At higher concentrations (D?6?1016 cm-2) the surface completely is covered by Ca atoms. It was shown that deposition of ?=10 thick Si single layer on CaF2 surface manifests island picture. The concentration of Ca and Si nano-scale phases on the surface of CaF2 and the band gap of the phases were investigated as a function of (h?) of passing light.

Authors : O. Blázquez,1,2 J. L. Frieiro,1,2 F. Bonet-Isidro,1,2 S. González-Torres,1,2 J. López-Vidrier,3 C. Guillaume,4 X. Portier,4 C. Labbé,4 P. Sanchis,5 S. Hernández,1,2 B. Garrido1,2
Affiliations : 1MIND, Department of Engineering: Electronics, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona, Spain 2Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Av. Joan XXIII S/N, E-08028 Barcelona, Spain 3Laboratory of Nanotechnology, Department of Microsystems Engineering (IMTEK), Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 103, D-79110 Freiburg, Germany 4CIMAP Normandie Univ, ENSICAEN, UNICAEN, CEA, CNRS, 14050 Caen, France 5Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain

Resume : The fast scaling in electronics has made emerge a great interest in memory technologies, being the resistive random access memory (ReRAM) one of the most promising ones. In this kind of devices, the formation and destruction of conductive filaments across a dielectric allows switching between a high resistance state (HRS) and a low resistance state (LRS). This is the so-called resistive switching (RS) effect. In metal oxides, this structural modification is typically governed by oxygen vacancies, being the combination of the applied voltage and the injected current necessary to trigger this process. On the other hand, optical switching has been achieved via phase transition, in materials like VO2, in which the variation of the transmittance of the active layer occurs under external stress. However, in this case, the light does not directly influence the RS process, being only used to read the optical state. In this work, the RS properties of ITO/ZnO/p-Si devices are studied in dark and under light conditions. The application of light allowed decreasing the required voltage to induce the RS from HRS to LRS due to the injection of extra carriers from the p-Si substrate, allowing to have this transition at a reading voltage. Different wavelengths and optical powers were also employed, determining the corresponding dependence and permitting to optimize the parameters to obtain a light-triggered RS device.

Authors : F. Bonet-Isidro,1,2 J. L. Frieiro,1,2 O. Blázquez,1,2 J. López-Vidrier,3 S. González-Torres, 1,2 C. Guillaume,4 X. Portier,4 C. Labbé,4 P. Sanchis,5 S. Hernandez,1,2 B. Garrido1,2
Affiliations : 1MIND, Department of Electronics and Biomedical Engineering, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona (Spain) 2Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Av. Joan XXIII S/N, E-08028 Barcelona (Spain) 3Laboratory for Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 103, D?79110 Freiburg (Germany) 4CIMAP Normandie Univ, ENSICAEN, UNICAEN, CEA, CNRS, 14050 Caen, France 5Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain

Resume : Resistive switching (RS) is a property exhibited by some materials that consists in the change of their resistance when a voltage is applied to them, which allows these materials to be cycled between two or more resistive states. In the literature, different oxide compounds, such as TiO2, HfO2, SnO2, or ZnO, have been employed as active layers in resistive devices. In particular, ZnO has recently attracted great attention because it is a non-toxic and earth abundant material with excellent transparency in the visible range. However, the oxygen out-diffusion in each RS cycle limits the endurance of the devices. A method for improving the RS properties of ZnO consists in doping it with rare earths. The oxygen absorption of these materials would increase the stability and resistance ratio between the high and low resistance states of the devices. In this work, the electrical and optical properties of ZnO devices deposited by sputtering, undoped and doped with Tb ions, are reported. Both types of devices present RS behavior, however, the doped ones allow working at lower current which, in turn, also increases their endurance, with a large resistance ratio between ON and OFF states (10E9). The conduction mechanisms are discussed in terms of their resistance state and the presence of Tb ions. Finally, the doped devices also exhibit light emission only in the low resistance state (ON state), which allows the optical reading of their resistive state.

Authors : Clément Majorel, Peter R. Wiecha, Caroline Bonafos, Vincent Paillard, Christian Girard
Affiliations : CEMES-CNRS, Université de Toulouse, 29 rue Jeanne Marvig, BP 94347, F-31055 Toulouse, France

Resume : Conventional plasmonics is performed with nanostructures of metallic materials such as gold or silver. Nevertheless, during the last ten years, a great deal of research has been conducted on non-metallic materials, for example by using oxides or hyper-doped semiconductors. Usually, it is possible to select the plasmonic resonance frequencies of a nanostructure by changing its shape, size or environment. Currently, this new type of materials allows us to adjust the resonance frequency by modifying the doping concentration introduced inside these structures. In particular, unlike with metallic materials, which exhibit resonances in the visible range, hyperdoped semiconductors have an adjustable plasmon resonance in the middle or far infrared range. In a first step, to define the new optical index of the doped materials we include an additional contribution characterized by a Drude model. In a second stage, we deduct the localized surface plasmon resonance of doped nanostructures by using the Green Dyadic Method (GDM). We deduce the localized surface plasmon resonance of highly doped nanostructures using the GDM. This method is based on solving of self-consistent equations and allows us to deduce the optical response of doped nanostructures of complex shapes. We apply the GDM to the computation of far-field optical spectra and near field images.

Authors : M. N. Mayakova**, O.B. Petrova*, V.A. Smirnov*, A.V. Khomyakov*, V.V. Voronov**, I. Ch. Avetissov*
Affiliations : * - Department of Crystals Chemistry and Technology, Dmitry Mendeleev University of Chemical Technology of Russia (MUCTR), Moscow, Russia ** - Prokhorov General Physics Institute RAS, Moscow, Russia

Resume : According to the known of PbF2?REF3 (RE= rare-earth elements) phase diagrams wide regions of crystallization of the fluorite-type cubic phase are observed, but at temperatures lower 650°? the data on synthesis conditions and functional parameters of cubic PbF2 based solid solutions are not presented. The homogeneity limits of the solid solutions in the PbF2?REF3 systems at 650°? were determined as 20-25 mol % of RE fluoride. The solid solutions in the PbF2?REF3 (RE=Eu, Er) systems were synthesized two techniques: the solid-phase method; the coprecipitation from aqueous solutions in the composition range from 0 to 100 mol% of REF3. The structures of solid solutions have been investigated. It was found that an increase of RE concentration in the initial solution during the coprecipitation promoted the crystallization of the high-temperature cubic phase of solid solutions based. It was determined that >7 mol% europium in the solution was enough to obtain the high-temperature cubic phase. The photoluminescence spectra of solid solutions obtained have been studied. The luminescent centers of Eu3 in solid solutions obtained by the solid-state synthesis had a greater symmetry than those obtained by the coprecipitation from aqueous solutions. This research was financially supported by the grant (10.4702.2017/BC).

Authors : H.Kacem, Ah. Dhahri, E. Dhahri, J. Dhahri, K. Khirouni, K. Taibi.
Affiliations : Laboratoire de la Matière Condensée et des Nanosciences, Département de Physique, Faculté des Sciences de Monastir, Université de Monastir, 5019, Tunisia. - Faculté des Sciences, Monastir, Université de Monastir, Avenue de l'environnement, 5019, Monastir, Tunisia. - Laboratoire de Physique Appliquée, Faculté des Sciences de Sfax, BP 1171, Université de Sfax, 3000, Tunisia Laboratoire de Physique Appliquée, Faculté des Sciences de Sfax, BP 1171, Université de Sfax, 3000, Tunisia Laboratoire de la Matière Condensée et des Nanosciences, Département de Physique, Faculté des Sciences de Monastir, Université de Monastir, 5019, Tunisia. Laboratory of Physics of Materials and Nanomaterials Applied to the Environment, Faculty of Sciences of Gabes, University of Gabes, City Erriadh, 6079, Gabes, Tunisia. Laboratory of Materials Science and Engineering, Faculty of Mechanical Engineering and Process Engineering, University of Science and Technology Houari Boumediene, BP32 El Alia, Bab Ezzouar, 16111, Algiers, Algeria.

Resume : Lead free ceramic composition of Ca0.8Nd0.05K0.1Ti0.85Nb0.15O3, were synthesized by conventional solid-state sintering. The crystallographic structure was studied by X-ray diffraction experiments and Rietveld refinement revealed that our sample crystallizes in orthorhombic structure with Pbnm space group. The approximate grain size was found from experiment?s scanning electron microscopy. Using impedance spectroscopy technique, the dielectric and electrical properties were obtained from the conductance and capacitance measurements over a broad frequency range of 100 Hz-1 MHz and temperatures range of 570- 610 K. Nyquist plots showed that the dielectric response can be fitted by Cole-Cole model and represented by an equivalent circuit. Electric modulus formalism was employed to study the relaxation dynamics of charge carriers. The values of total conductivity for our sample were well fitting by the Jonscher?s universal law. Additionally, the dielectric measurements were confirmed by the photoluminescence spectra.

Authors : P.-E. Coulon1, J. Amici1, M.-C. Clochard1, I. Monnet2, C. Grygiel2, V. Khomenkov2, C. Dufour2, M. Kociak3, L. Largeau4, G. Rizza1
Affiliations : 1LSI, Ecole polytechnique, Route de Saclay, 91128 Palaiseau Cedex, France 2CIMAP, Boulevard Henri Becquerel, 14070 Caen Cedex 5, France 3LPS, Bâtiment 510, Université Paris Sud XI, 91405 Orsay, France 4C2N, Avenue de la Vauve, 91120 Palaiseau, France

Resume : The importance of the ion-beam shaping technique relays in its unique capability to modify the morphology of nanoparticles (NPs) embedded within an amorphous host matrix. Consequently, ion-shaping technique is a route for downscaling the engineering of embedded NPs with a precision that is barely reachable with standard techniques. In this sense, the use of ion-shaped plasmonic crystals opens the way for advanced applications in the fields of bio-sensing or surface field enhanced spectroscopies (SERS). Although nowadays a vast literature exists on the ion-shaping technique, the deformation of hollow nanoparticles (HNPs) is still unknown. As spherical HNPs have a localized surface plasmon resonance between 700 and 800 nm, thus their elongation allows to explore deeper regions of the near-infrared region of the optical spectrum. Here, we show that swift heavy ion irradiation can be used to obtain spatially oriented hollow NPs, with an aspect ratio increasing over 2. The deformation mechanisms have been studied by changing both the dimension of the HNPs and the thickness of the metallic shell. Experimental results are interpreted using the 3D-TS code. Finally, plasmon mapping is nanometer-scale spatial resolution is obtained by Electron Energy Loss Spectroscopy (EELS). This work represents a step forward for the development of an alternative route for the controllable fabrication of a whole family of nanostructures in vertical geometry with topologically tunable properties.

Affiliations : School of Nanoscience and Nanotechnology, IIT Kharagpur-721302, India; Department of Civil Engineering, IIT Kharagpur-721302, India.

Resume : Galvanic replacement reaction (GRR) is a widely used powerful synthesis technique to produce different hollow and porous nanostructures. In the present work, As(0) nanoparticles of two different size ranges As1 and As2 (e.g. 50±7 and 70±10 nm) are synthesized by sodium borohydride reduction of arsenite under controlled pH with two different approach. It has been found that the formation of As(0) is depending upon two factors which are first temperature and second is time. Two different size As(0) nanoparticles achieved by performing reduction in two different temperature condition, that is 10° C and 40°C. In case of room temperature preparation of As(0), time needs to grow up from smaller to bigger size. Now these nanoparticles are subsequently used as templates for GRR reaction to produce two different sized porous silver nanoparticles (HSNPs), which are designated as AgNP1 and AgNP2, with average diameter 55???and 72???nm, respectively. The important aspect of this preparation is that no external stabilizer has been used. The unique feature of the reduction of arsenite to As(0) and not to AsH3, is the control of medium pH at 7-9. Now the use of AgNP1 and AgNP2 in homogeneous phase is restricting them to recollect and reuse properly. So a soft solid template, Surfactant-modified silica (SMS) having positive charge in the surface is taken and the ionic attraction between negatively charged surface of AgNP1 and AgNP2 which is arises due to the stabilization of in situ H2AsO4?, helps attaching in the surface of the SMS to produce two different heterogeneous catalysts SMS-Ag1 and SMS-Ag2. The beauty of this method is though catalysts are transferred into different phases, that is from liquid to solid but the sizes remains unchanged or there is no agglomeration takes place, as it is very normal while no external stabilizer is used to prepare Nanoparticles. The catalytic reduction of 4-nitrophenol (4-NP), which is a toxic compound used in many industries, to 4-aminophenol (4-AP), an industrially important compound is a well studied model reaction. The size dependent catalytic activities of the as-prepared HSNPs have been examined on the reduction of 4-NP to 4-AP in the presence of sodium borohydride. While both the nanoparticles exhibit excellent catalytic activity, the smaller particles (SMS-Ag1) are observed to be more effective. The reaction is carried out with various catalyst doses and initial 4-NP concentrations and the reaction follows first order kinetics in all cases. The turn over frequency (TOF) for the catalytic reaction using SMS-Ag1 and SMS-Ag2 suggests that SMS-Ag1 bears ~3 times higher catalytic activity compared to that of SMS-Ag2. The reusability of both catalyst SMS-Ag1 and SMS-Ag2 also checked.

Authors : A. Akilbekov1, A. Dauletbekova1, F. Komarov2, Z. Baimukhanov1, A. Kozlovskii3, L. Vlasukova2, R. Balakhaeva1, Sh. Giniyatova1, A. Usseinov1
Affiliations : 1L.N. Gumilyov Eurasian National University, Astana, Kazakhstan 2Belarus State University, Minsk, Belarus 3AB of Institute of Nuclear Physics, Astana, Kazakhstan

Resume : The purpose of this research is to obtain CdTe nanocrystals by electrochemical deposition (ECD) in a-SiO2/Si -n track template. The structure of a-SiO2/Si -n was obtained by thermal oxidation of Si substrate at 900 ??. The thickness of SiO2 layer was 600 nm. The a-SiO2/Si -n was irradiated on a DC-60 accelerator (Astana) with Xe ions 200MeV, ? = 108 ion/cm2, the subsequent etching in HF solution led to the creation of nanopores. A conventional electrolytic cell was used for ECD. The voltage on the electrodes was 1.5V, t = 5 min. ECD of CdTE was carried out on two different solutions: 1) 1? CdSO4 + 1mM TeO2, pH =2; 2) 1? CdCl2 + 1mM TeO2. pH =2. The surface of the samples was examined before and after ECD by SEM JSM 7500F. X-ray diffraction analysis of the samples was carried out on a D8 ADVANCE ECO. The use of chloride and sulphate electrolyte leads to the formation of the dominant amorphous phase of CdTe over the crystalline hexagonal phase. Subsequent annealing leads to the dominance of CdTe nanocrystals.

Authors : Borisyuk P. V., Lebedinskii Yu. Yu., Vasilyev O.S.
Affiliations : National Research Nuclear University MEPhI (Moscow Engineering Physics Institute); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow Institute of Physics and Technology (State University); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)

Resume : The efficiency of energy generation of modern energy sources based on the use of thermal energy is currently of increased interest. There is a need to create new thermophotovoltaic (TPV) converters with increased efficiency in the near infrared range. We propose to study a special TPV material, namely, a thin nanostructured film consisting of metal nanoparticles (2-15 nm in diameter) with the spatial ordering of nanoclusters by size. This system is an ensemble of densely packed metal nanoclusters with a gradient size distribution of nanoparticles deposited on the surface of silicon oxide. A key feature of the system is that the presence of the size dependence of the Fermi energy leads to the spatial redistribution of the charge in the system as a whole. That means that the average size of metal nanoparticles in the conducting system of nanoparticles in contact with each other monotonically changes in the selected direction, the potential difference is observed in the same direction. The appearance of a photoelectron in this system leads to the flow of the electron in the direction of the potential gradient. Since nanoclusters are metal, this provides the ability to detect photons of different wavelengths and provides a wide spectrum of radiation absorption. The obtained preliminary results on the formation and study of the properties of nanocluster films are discussed. The study of such systems may enhance energy efficiency and energy saving of thermal power sources.

Authors : O.B. Petrova*, A.S. Sologub*, D.A. Velichkina*, M.P. Zykova*, A.V. Khomyakov*, M.A. Uslamina**, K.N. Nischev**, A.A. Pynenkov**, I. Ch. Avetissov*
Affiliations : * Department of Crystals Chemistry and Technology, Dmitry Mendeleev University of Chemical Technology of Russia, Moscow, Russia ** Physics and Chemistry Institute National Research Mordovia State University, Saransk, Russia

Resume : Oxyfluoride glass ceramics (GCs) combine the best properties of crystalline fluorides and oxide glasses, which make them promising for new laser materials when the cubic phase of PbF2 in GCs is activated by rare-earth (RE) ions. 7-10 mol% of RE fluoride is enough for the cubic phase stabilization. As stabilizing agents we used La(Lu)F3 which did not generated luminescence. NdF3 was used as an activator which formed efficient luminescence centers in GCs. The 67PbF2?30B2O3-3REF3 glasses in which REF3 consisted of 0.2-3 mol% of NdF3 + 0-2.8 mol% LaF3(or LuF3) have been synthesized. DTA showed strong difference in characteristic temperatures and thermal effects depending on Nd/La ratio. GCs were obtained by the controlled crystallization of glasses. The total RE concentration in the crystalline phase varied from 11-12 at% for Pb(1-x)La/Nd(x)F(2+x) to 17-18 at% for Pb(1-x)Lu/Nd(x)F(2+x). Comparison of luminescence spectra of glasses, GCs and crystalline samples showed that there is a splitting of the 0-0 line of the interstark of 4F3/2?4I9/2 transition in Nd3+ ion in the case of the GCs made from co-doped glasses, which is observed in crystals. Thus, it has been demonstrated that it was possible to stabilize a cubic phase based on PbF2 simultaneously by several RE dopants and to obtain GCs with a crystalline phase in which the concentration quenching was reduced compared to GCs doped with a single activator. Supported by the grant (10.4702.2017/BC).

Authors : Soon-kyu Cha1,2 ShinYoung Jeong1,3, JoonHyun Kang1, Young Dong Kim2, Sungjun Kang4, Il Ki Han1,2
Affiliations : 1Nanophotonics Research Center, Korea Institute of Science and Technology; 2Department of Converging Science and Technology, Kyunghee University; 3School of Electrical Engineering, Korea University; 4Department of Advanced Materials Engineering for Information and Electronics, Kyunghee University

Resume : Colloidal quantum dots (QDs) have been considered as an alternative material to the amorphous silicon for the active semiconductor in a photodetector due to size-dependent bandgap engineering, relatively high quantum yield, and low-cost solution processing. On the other hand, oxide semiconductors have a high potential for transparent electronics due to their wide band gaps and high field-effect mobility. In this study, we fabricated ZnO phototransistors with multi-photoactive QD channels using patterned ZnO film by PDMS surface engineering and patterned QDs by charge-assisted layer-by-layer method. The average off-current was reduced from 10^(-10)A to 10^(-11)A and the leakage current was effectively suppressed. The photocurrent generated by the stepwise activated QDs was able to distinguish various wavelengths in the visible range. These results demonstrate the potential of patterned ZnO and QD devices to operate with low power and as transparent and flexible full-color image sensors.

Authors : Thi Hai Yen Vu, Marc Hayoun, Giancarlo Rizza
Affiliations : Laboratoire des Solides Irradiés (LSI) Ecole polytechnique

Resume : We investigate the dissolution law of metallic nanoparticles (NPs) under sustained irradiation. The system is composed of isolated spherical gold NPs (4?100 nm) embedded in an amorphous silica host matrix. Samples are irradiated at room temperature in the nuclear stopping power regime with 4 MeV Au ions for fluences up to 8e16 cm-2. Experimentally, the dependence of the dissolution kinetics on the irradiation fluence is linear for large NPs (45?100 nm) and exponential for small NPs (4?25 nm). A lattice-based kinetic Monte Carlo (KMC) code, which includes atomic diffusion and ballistic displacement events, is used to simulate the dynamical competition between irradiation effects and thermal healing. The KMC simulations allow for a qualitative description of the NP dissolution in two main stages, in good agreement with the experiment. Moreover, the perfect correlation obtained between the evolution of the simulated flux of ejected atoms and the dissolution rate in two stages implies that there exists an effect of the size of NPs on their dissolution and a critical size for the transition between the two stages. The Frost-Russell model providing an analytical solution for the dissolution rate, accounts well for the first dissolution stage but fails in reproducing the data for the second stage. An improved model obtained by including a size-dependent recoil generation rate permits fully describing the dissolution for any NP size. This proves, in particular, that the size effect on the generation rate is the principal reason for the existence of two regimes. Finally, our results also demonstrate that it is justified to use a unidirectional approximation to describe the dissolution of the NP under irradiation, because the solute concentration is particularly low in metal-glass nanocomposites

Authors : R. A. Puglisi*, C. Bongiorno, G. Borgh1, E. Fazio1, C. Garozzo, G. Mannino, F. Neri1, G. Pellegrino, S. Scalese, and A. La Magna
Affiliations : CNR Istituto per la Microelettronica e Microsistemi, Strada Ottava 5, Zona Industriale, 95121 Catania, Italy; 1Dipartimento Scienze Matematiche ed Informatiche, Scienze Fisiche e Scienze della Terra, Università degli Studi di Messina, F. Stagno d’Alcontres, 31, 98166 Messina, Italy.

Resume : Si nanowires are largely studied for photovoltaics because their optical properties improves the light harvesting, allow decoupling the photon absorption from the carrier collection paths and act as waveguides, making light coupling efficient. Among the synthesis methods the most known for Si-NWs is the Vapor Liquid Solid growth in Chemical Vapor Deposition chambers (VLS-CVD) using gold as catalyst. After the growth, the catalyst particles remain on the tip of the Si-NWs, representing an issue for the cell performance, because Au creates deep trap in the Si band gap. So it is essential to properly remove the Au particles from the SiNWs before the matrix deposition. Most of methods proposed so far to remove Au offer low removal efficiency, strongly oxidize the Si-NWs sidewalls or produce structural damage on the Si-NWs inner core. A detailed physical-chemical characterization on the as-grown Si-NWs and on their surface is presented. A 1-2 nm thick shell covering the Au tip, acting as a barrier for the Au removal, is found and its chemical composition is studied. The layer formation is discussed in terms of the heating/cooling and consequent phase separation processes taking place in the eutectic particles. A new approach fast and efficient for the Au removal is then proposed. The characterization after the chemical etching is also performed to monitor the removal efficiency and the possible modifications in the Si-NWs morphological characteristics.

Authors : Vasilica ?ucureanu1,2, Alina Matei1, Andrei Avram1, Iuliana Mihalache1, Marian C?t?lin Popescu1, Cosmin Romani?an1, Bianca ?încu1, Marioara Avram1, Daniel Munteanu2
Affiliations : 1National Institute for Research and Development in Microtehnologies (IMT-Bucharest), Erou Iancu Nicolae Street, 126A, 077190, Bucharest, Romania; 2Transilvania University of Brasov, Department of Materials Science,29 Eroilor Blvd, 500036, Brasov, Romania

Resume : This paper presents studies on the synthesis and characterization of Eu doped Y2O3 red phosphor and the improvement of properties by anchoring Au nanoparticles to the surface of the phosphor. Phosphor samples were obtained by cation precipitation and sintering at 900°C, followed by in situ modification of the Y2O3:Eu surface by anchoring of gold nanoparticles following a process based on the Turkevich method. The quality of red phosphor particles and the Au-Y2O3:Eu composite has been studied from structural, morphological and optical point of view by Fourier Transform Infrared (FTIR) spectrometry, scanning electron microscopy (SEM), x-ray diffraction (XRD), and photoluminescence (PL) spectroscopy. By modifying the surface with Au nanoparticles, a high purity red phosphor was obtained, without altering the crystalline structure of Y2O3:Eu. The use of Au nanoparticles has made it possible to improve optical properties as a result of the decline in the agglomeration tendency. The developed Au-Y2O3:Eu nanocomposites have improved properties and can be used as a single host for red light emission in optoelectronic devices.

Authors : Dmitry Zablotsky (a,b), Vladimir Kuzovkov (b), Eugene Kotomin (b)
Affiliations : (a) Institute of Physics, University of Latvia, Latvia; e-mail:, (b) Institute of Solid State Physics, University of Latvia, Riga, Latvia

Resume : Efficient ambient energy scavenging exploiting piezo-/pyroelectric properties of ABO3 perovskites to power low-energy devices is an attractive green energy strategy. In turn, the colloidal processing of the nearly monodisperse and highly crystalline single-domain nanocubes of BaTiO3, SrTiO3 perovskites and a range of their solid solutions is a promising route to produce superlattice assemblies for integration into nanostructured ferroelectric devices [1] with improved properties. Controlling the local behaviour of nanocrystals is imperative for fabricating highly-ordered assemblies, whereas the current picture of nanoscale polarization suggests a potential presence of significant electrodipolar interaction [2]. However, its role in the condensation of perovskite nanocubes remains unknown. We report the microstructural characterization of osmotically densified ensembles of ferroelectric nanocubes obtained via numerical simulations exploiting discrete element method (DEM) coupled with particle-particle particle-mesh (P3M) approach for computing long-range dipolar interactions. Our results indicate that the long-range positional and orientational correlations seem to be highly sensitive to the presence of dipoles, which could be a challenge to produce ordered assemblies of some nanoperovskites. Exploring the features of mesoscale disorder we find characteristically similar behavior in a wide array of systems. We show that in fact for solubilized BaTiO3 nanocubes the polarization screening must be complete without appreciable dipole moment (below a few ~ kT), whereas stray interactions from incompletely screened surface charges are likely major sources of disorder in self-assembled architectures of some nanoscale perovskites, most specifically SrTiO3. 1. Kato et al., Appl. Phys. Lett. 101, 012901 (2012) 2. Polking et al., Nat. Mater. 11, 700?709 (2012)

Authors : Jianxiong Zhao, Xian Chen, Bing Chen, Feng Wang
Affiliations : City University of Hong Kong

Resume : Fine tuning the preferentially oriented shell growth on selective facets of core nanoparticle is indispensable for synthesizing complex core-shells which has exceptional luminescent properties in biological applications. However, the kinetics of shell growth and the variation of emissions intensity and color at each growth stage remains unclear in NaREF4 (RE= rare earth) upconversion core-shells. Compared to uniform shell growth with sphere-like morphology, we show that the morphologies of shell with non-uniform surface energy underwent different stages as growing reaction proceed. The morphologies changing are revealed by using high-resolution transmission electron microscopy (TEM) and conventional TEM. The phase evolution is characterized by wide angle X-ray diffraction with quantitative analysis. Thickness and core dimension dependent shell growth and upconversion emission properties has been investigated. The spectroscopy analysis shows that the emission is reliant on both core and shell shape and dimensions. Moreover, the emissions variation is correlated to morphology change, which is supported by XRD and TEM analysis.

Authors : Jinhyuk Yoo, Soonkon Kim, Byoungdeog Choi
Affiliations : Sungkyunkwan university and Samsung Electronics ; Sungkyunkwan university ; Sungkyunkwan university

Resume : The charge trapping properties of multilayered HfO2/Al2O3 high-k stacks with each different thickness ratio were investigated in order to improve the charge migration issues in charge trapping flash memories. The high-k layers, HfO2 and Al2O3, were deposited by an atomic layer deposition method, and the charge trapping layers of each structure were composed of HfO2/Al2O3 with the thickness ratios of 3: 1, 1: 1, and 1: 3, respectively. And then post deposition annealing was performed in N2 ambient at 800? for 30 minutes. The interfaces between HfO2/Al2O3 laminated films play an important role in charge storage properties and the improvement of the charge loss. Especially, due to the difference in a band gap between HfO2 and Al2O3, HfO2 forms a deep quantum well and Al2O3 acts as a barrier to prevent the loss of electrons captured in the charge trapping layer. Also, the number of interfaces and the ratio of appropriate laminate film thickness are important factors for obtaining good data retention characteristics. Experimental results show higher charge storage density and a larger memory window of 10V in the structure with the thickness ratio of the HfO2/Al2O3=1:1 and many interfaces. Also a lower leakage current and a smaller charge loss rate of 14.2% which are responsible for the excellent retention performance are obtained in this structure. The proposed multilayered high-k trap structure may be very useful in future charge trap flash memory device application.

Authors : Xinqiang Pan,1,2 Yao Shuai*,1 Chuangui Wu,1 Lu Zhang,3 Hongliang Guo,3 Hong Cheng,3 Yun Peng,1 Shijun Qiao,1 Wenbo Luo,1 Tao Wang,1 Huizhong Zeng,1 Jianwei Zhang, 2 Wanli Zhang,1 Xin Ou,4 Nan Du,5 and Heidemarie Schmidt5,6
Affiliations : 1. State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China; 2. Institute of Technical Aspects of Multimodal Systems (TAMS), Department of Informatics, Universität Hamburg, D-22527, Hamburg, Germany; 3. The Center for Robotics, University of Electronic Science and Technology of China, Chengdu 611731, China; 4. State Key Laboratory of Functional Material for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China; 5. Fraunhofer-Institut für Elektronische Nanosysteme, Abteilung Back-End of Line, Technologie-Campus 3, 09126 Chemnitz, Germany; 6. Leibniz-Institut für Photonische Technologien e.V. (IPHT), Albert-Einstein-Str. 9, 07745 Jena, Germany

Resume : Recently, because of the similar behavior with synapse under stimuli, memristors became emerging building blocks for neuromorphic computing which will promote the future development of artificial intelligence and the investigation on memristors attracted great attention. However, the in-situ online training of artificial neural network with memristors still suffers some problems because of the challenge in device property engineering. On the same thin film, the device-to-device uniformity of voltage required for memristor?s electro-forming and switching is difficult to achieve currently through the traditional deposition technique of thin film. Thus, a transistor was needed to be connected with each memristor to solve this problem, which will have negative effects on higher density integration and will also increase the energy consumption. In this work, single-crystalline LiNbO3 (LNO) thin films fabricated by crystal-ion-slicing (CIS) technique were used to provide an ideal environment without the co-existence of grain and grain boundaries and without randomly introduced oxygen vacancies (OVs), and the device property engineering by post-processing was conducted on such thin films. It has been proved that the uniformity of voltage required for memristor?s electro-forming and switching can also be improved by this way [1]. The plasticity of the memristor is based on the memristive behavior, and it is significant for the neuromorphic computing. Different plasticity properties were required in different cases of neuromorphic computing, so plasticity properties need to be controllable and tunable. Nowadays plasticity is controlled externally by transistor connecting with the memristor. The negative effects of connecting a transistor with memristor have been mentioned above. Here, we we tune the intrinsic plasticity properties of memristors by new device property engineering and avoid the usage of transistors. In present work, Ar irradiation was conducted on the single-crystalline LNO thin film. And the memristive behavior was observed and investigated, which demonstrated that Ar irradiation is an effective post-processing method to introduce OVs into the thin film. Local Ar irradiation was realized on single-crystalline LNO thin film. Micro Ar -irradiated zones were fabricated. Then memristors with different numbers of micro Ar -irradiated zones were fabricated. By changing the number of micro Ar -irradiated zones within the memristor, the plasticity property have been shown to be tunable. The memristors with different plasticity property were used in the same on-line training process for the basic function of artificial neural network (linear regression) respectively. The performances of artificial neural network with different memristors were compared. The results show the effects of the tuning of plasticity property. Reference? [1] X. Pan, Y. Shuai, C. Wu, W. Luo, X. Sun, H. Zeng, S. Zhou, R. Böttger, X. Ou, T. Mikolajick, W. Zhang, H. Schmidt, Rectifying filamentary resistive switching in ion-exfoliated LiNbO3 thin films, Applied Physics Letters, 108 (2016) 032904.

Authors : Donaev S.B., Umirzakov B.E.
Affiliations : Tashkent state technical university

Resume : The thickness of the Si films on the surface of the CaF2 (111) substrates varied within 1-10 monolayers. To obtain epitaxial structures, after each deposition cycle, heating to a temperature of 800?850 K was carried out for 30 min. The results of the analysis of SEM and DME images showed that when 1 monolayer, nanocrystalline Si phases with diameters d = 10 -15 nm are formed, and the distances between their centers are 50 -70 nm. At 8 monolayer, the surface dimensions of the phases increase to 30?50 nm, and their height h is 1.5?2 nm. When 10 monolayer, a continuous film is formed. At 10 monolayer, reflexes 7x7, characteristic of single-crystal Si (111) samples, appear in the DBE pattern. It can be assumed that the growth of Si occurs epitaxially. These results can be explained as follows: As increases of monolayer from 1?5 monolayers, the phase sizes and the degree of CaF2 surface coverage by Si atoms monotonously increase, in particular, for 3 monolayer, the surface diameters of nanophases are 20?25 nm, and their height is h = 1?1.2 nm. Apparently, starting with 5 monolayer, along with a slight increase in the size of the existing phases, new phases begin to appear. Consequently, the surface diameter of the phases changes in a wide range: from 30 to 50. At 8 monolayers, the edges of the neighboring phases (islands) of Si begin to overlap with each other and a film with an uneven thickness is formed. At 10 monolayers, a uniform continuous epitaxial film with a thickness of 1.5-2.0 nm is formed.

Authors : Seon Joo Park, Oh Seok Kwon
Affiliations : Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Republic of Korea

Resume : Various human sensory-mimicking methodologies have been developed as electronic brains, tongues, skin, and ears for replacing human six senses. However, no significant achievements have been made in discriminating odorants because the chemical structures of odorants have a difference with a carbon atomic resolution. Moreover, there are no electronic noses with dual-detectors for odorant mixture. In this study, we demonstrated natural receptors-conjugated nanobioelectronic noses for multi-discrimination in odorant mixture. First, we introduced how to design human olfactory natural receptors and graphene nanohybrids by microelectromechanical system. The fabrication protocols of nanobioelectronic noses were introduced and they were characterized by HR-TEM, Raman, optical measurement, I-V and transfer curve. The real-time responses from nanobioelectronic noses were measured with current signal in field-effect transistor system, resulted into the high-performance odorant discriminatory ability in mixtures. In addition, field-induced signals from the nanobioelectronic noses were monitored and provided high sensitivity and selectivity toward target odorants (minimum detectable level: 0.1 fM). This research can be applied for foods, odorants and healthcare industries.

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Optics, Photonics, Plasmonics : Tom Gregorkiewicz
Authors : Christophe Delerue
Affiliations : ULille, CNRS, Centrale Lille, ISEN, UPHF, UMR 8520 - IEMN, F-59000 Lille, France

Resume : After 30 years of intense research, colloidal semiconductor nanocrystals are presently employed in a certain number of technologies which can be integrated into grand-public applications. Due to their small size (typically below 10 nm), these nanocrystals behave as quantum dots for the electrons (holes) and their optical properties are strongly influenced by quantum confinement effects. Up to now, semiconductor nanocrystals have been mainly studied for their linear optical response, either in absorption or luminescence. In this talk, I present numerical simulations showing that semiconductor nanocrystals could be of high interest for their non-linear response. I argue that recent progress in colloidal chemistry could be used to design nanocrystals characterized by strongly non-linear optical properties and I propose several strategies allowing to reach this goal.

Authors : Johann Toudert
Affiliations : Laser Processing Group, Instituto de Óptica, IO-CSIC, Madrid, Spain

Resume : Functional materials enabling a perfect trapping of light are appealing for a broad variety of applications, including contactless sensing and energy conversion. However, this may require light to be trapped over spectral windows with very different widths: narrowband for contactless sensing versus broadband for energy conversion. Although such very different spectral responses are at the reach of metamaterials based on noble metal or standard semiconductor nanostructures tailored by multistep lithography processes, this approach is not ideal for a low-cost upscaling. In here, strategies will be proposed to achieve equivalent or even more impressive light trapping - based properties in lithography-free nanocomposite metamaterials. First, it will be demonstrated that, by harnessing the hybrid plasmonic-photonic modes of noble metal nanoparticles in dielectric cavities, high-resolution contactless sensing can be achieved while avoiding optical losses in the metal. [1,2] Furthermore, it will be explained how substituting noble metals and standard semiconductors by emergent semi-metal and topological insulator materials enables perfect light trapping tuned from the ultraviolet to the far-infrared in ultra-thin nanocomposite metamaterials for energy conversion applications: photocatalysis, photodetection and thermal emission. [3-6] [1] Baraldi et al., Adv. Mater. Int. 5, 1800241 (2018) [2] Toudert et al., ACS Photon. 2, 1443 (2015) [3] Toudert et al., J. Phys. Chem. C 11, 3511 (2017) [4] Toudert et al., Opt. Mater. Express 7, 2299 (2017) [5] Toudert et al, Opt. Express 26, 34043 (2018) [6] Ghobadi et al., ACS Photon. 5, 4203 (2018)

Authors : Miguel Alvarez1, Marina Garcia1, Fatima Cabello1, Emmanuel Haro-Poniatowski2, Rosalia Serna1, and Jan Siegel1
Affiliations : 1. Laser Processing Group, Instituto de Óptica, IO-CSIC, Serrano 121, 28006 Madrid, Spain 2. Departamento de Física, 2 Departamento de Química, Universidad Autónoma Metropolitana Iztapalapa, Av. San Rafael Atlixco No. 186, Col. Vicentina, C.P. 09340, México D. F. México

Resume : Nanocomposite systems based on bismuth nanoparticles (Bi NPs) have received a growing interest due to the demonstration of plasmon-like resonances that can be tuned in the visible-UV region, and that have found applications for integrated photonic devices, surface enhanced spectroscopy and plasmonic enhanced photocatalysis.[1,2] Furthermore, due to the low melting temperature of Bi, these systems are also candidates for its use as optical switches by profiting from the different optical properties of solid and liquid Bi [3]. Here we study the solid-liquid phase change of Bi NPs embedded in amorphous aluminium oxide film upon nanosecond laser excitation by using single pulse real time reflectivity measurements with nanosecond resolution. The changes of the reflectivity reveal that melting takes place within the nanosecond pulse duration whereas cooling and solidification of the NPs occurs over time scales that are much longer than for bulk Bi. The solid-liquid switching time is found to depend on the nanoparticle density, and it can be controlled smoothly from 10 ns to 700 ns by adjusting the laser pulse fluence. The optical switching process is found to be repeatable more then 10,000 times without observable degradation. [1] J. Toudert, et al. J. Phys. Chem. C 121, 3511 (2017). [2] J. Toudert and R. Serna, Opt. Mater. Express 7, 2299 (2017). [3] M. Jiménez De Castro, F. Cabello, J. Toudert, R. Serna, and E. Haro-Poniatowski, Appl. Phys. Lett. 105, (2014).

Authors : S. Geiskopf (1), M. Stoffel (1), X. Devaux (1), E. André (2), C. Carteret (2), A. Bouché (1), M. Vergnat (1), H. Rinnert (1)
Affiliations : (1) Université de Lorraine, CNRS, Institut Jean Lamour, 54000 Nancy, France (2) Université de Lorraine, UMR CNRS 7564, LCPME, 405 rue de Vand?uvre, 54600 Villers les Nancy, France

Resume : In contrast to III-V or II-VI semiconductor alloys, group IV-V alloys have been the subject of much less attention up to now. Very recently, however, alloyed SiPx thin films have gained an increasing interest. Indeed, it was predicted theoretically that a monolayer of SiP is a direct bandgap semiconductor which could be promising for the development of 2D blue light emitting diodes. In this work, we investigate SiPx thin films prepared by evaporation under high vacuum. The films were prepared by co-evaporation of Si from an e-beam gun and P from a GaP decomposition source. The structural and optical properties were investigated by means of X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), vibrational spectroscopies (Infrared and Raman) and photoluminescence spectroscopy. After annealing at 1100°C, the structural characterizations reveal the presence of SiP grains crystallizing in an orthorhombic structure which coexist with Si polycrystals. To further characterize the SiP alloy, DFT calculations have been carried out to get a better understanding of the features observed in both infrared and Raman spectra. The calculated spectra are found to be in excellent agreement with the experimental results. Moreover, temperature dependent photoluminescence measurements strongly suggest that SiP is an indirect bandgap semiconductor with a bandgap energy of 1.47 eV. The obtained value is in good agreement with theoretical values found in the literature.

11:15 Plenary Session1    
12:30 Lunch    
Authors : Vincenzo Giannini, Paloma A. Huidobro, Simon Pocock
Affiliations : Instituto de Estructura de la Materia (IEM-CSIC), Consejo Superior de Investigaciones Científicas, Madrid, Spain; Physics Department, Imperial College London, Blackett Laboratory, London SW7 2AZ, United Kingdom; Physics Department, Imperial College London, Blackett Laboratory, London SW7 2AZ, United Kingdom

Resume : Topological photonic systems, with their ability to host states protected against disorder and perturbation, allow us to do with photons what topological insulators do with electrons. Topological photonics can refer to electronic systems coupled with light or purely photonic setups. By shrinking these systems to the nanoscale, we can harness the enhanced sensitivity observed in nanoscale structures and combine this with the protection of the topological photonic states, allowing us to design photonic local density of states and to push towards one of the ultimate goals of modern science: the precise control of photons at the nanoscale. Here, I will discuss our effort to move these topological concepts from electrons to light, in particular at the nanoscale. We will analyze the possibility of using prism coupling systems to excite and study Dirac Plasmons in topological insulators and I will show that topological insulators nanoparticles sustain a new kind of excitation when interacting with light. This is a topological localized surface plasmon polariton obtained perturbing the nanoparticle surface electron state with light. We will see preliminary experimental results on this previously unknown light-matter mode, which focused on bulk samples and thin films of topological insulators. These effects may be useful in the areas of plasmonics, cavity electrodynamics, and quantum information.

Authors : Nipun Sharma1, Marie Vangheluwe2, Alice Vermeulin2, Nathalie Destouches1
Affiliations : 1. Univ Lyon, UJM?Saint?Etienne, CNRS, Institut d Optique Graduate School, Laboratoire Hubert Curien UMR 5516, F?42023, Saint-Etienne, France. Email: 2. HID Global CID, 92150 Suresnes, France

Resume : Multiplexing color images that can be observed independently under white light in specific observation conditions is of great interest for applications to security, data storage or design. Few articles have recently demonstrated that dichroic plasmonic colors could be used to produce polarization sensitive dual-image multiplexing [1,2]. Here, we demonstrate that composite thin films containing anisotropic metallic nanoparticles can be used to print an encoded image that contains the information of three multiplexed images, which are revealed in non-polarized reflection or in polarized transmission using two different polarization angles. The proposed method can be applied to different nanoparticle shapes and implemented with different technologies. The demonstration is illustrated here by laser process, which allows printing centimetre scale images observable by eye [3]. The nanocomposite film is initially nearly color-less with metallic precursors in the form of ions, atoms and small nanoparticles (1-2 nm). A femtosecond laser grows and shapes metallic nanoparticles at the same time it tunes the size distribution and the spatial distribution of these nanoparticles in the film. The laser process results in the generation of micrometer size plasmonic nanostructured areas where the film birefringence and dichroism can be controlled at will, to produce unprecedented color gamuts that satisfy conditions for three-fold image multiplexing in three selected modes of observation. Each nanostructured area is characterized by a set of three colors corresponding to the colors exhibited in each selected mode. We further explain the conditions that the color gamuts in the three modes must fulfil to produce three-fold image multiplexing and how such conditions can be satisfied with plasmonic colors. Three-fold image multiplexing is shown using different color combinations [4]. Such laser processing is also applied to print dual multiplexed color images, for which more colors can be used. This methodology could be implemented with other technologies like electron beam lithography with a larger freedom on the choice of colors, along with a higher spatial resolution. Laser technologies however hold advantage for being more suitable for rapid and contactless printing on large surfaces. References 1- E. Heydari, J. R. Sperling, S. L. Neale and A. W. Clark, Plasmonic Color Filters as Dual?State Nanopixels for High?Density Microimage Encoding, Adv. Funct. Mater., 2017, 27, 1?6. 2- X. M. Goh, Y. Zheng, S. J. Tan, L. Zhang, K. Kumar, C. W. Qiu and J. K. W. Yang, Three-dimensional plasmonic stereoscopic prints in full colour, Nat. Commun., 2014, 5, 5361. 3- Z. Liu, M. Garcia-Lechuga, T. Epicier, Y. Lefkir, S. Reynaud, M. Bugnet, F. Vocanson, J. Solis, G. Vitrant and N. Destouches, Three-Dimensional Self-Organization in Nanocomposite Layered Systems by Ultrafast Laser Pulses, ACS Nano, 2017, 11, 5031?5040. 4- N. Sharma, M. Vangheluwe, A. Vermeulin, M. Bugnet, N. Destouches, Three-fold color image multiplexing with plasmonic films, under writing

Authors : A. Slablab, G. Rizza
Affiliations : Laboratoire des Solides Irradiés (LSI) Ecole polytechnique

Resume : Ion beam shaping is a novel and powerful tool to engineer nanocomposites with effective three-dimensional (3D) architectures. In particular, this technique offers the possibility to precisely control the size, shape and 3D orientation of metallic nanoparticles at the nanometer scale while keeping the particle volume constant. Here, we use swift heavy ions of xenon for irradiation in order to successfully fabricate nanocomposites consisting of anisotropic gold nanoparticle that are oriented in 3D and embedded in silica matrix. Furthermore, we investigate individual nanorods using a nonlinear optical microscope based on second-harmonic generation (SHG). A tightly focused linearly or radially-polarized laser beam is used to excite nanorods with different orientations. We demonstrate high sensitivity of the SHG response for these polarizations to the orientation of the nanorods. The SHG measurements are in excellent agreement with the results of numerical modeling based on the boundary element method.

Authors : F.Trad, X. Devaux, A. Bouché, M. Stoffel, M. Vergnat, H. Rinnert
Affiliations : Université de Lorraine, CNRS, IJL, F-54000 Nancy, France

Resume : Silicon nanocrystals (Si NCs) are the subject of an intense research activity, due to their optical and electronic properties. As in the case of bulk semiconductors, the fine tuning of their optical and electronic properties is related to the effective capability to control doping, i.e. incorporation of atoms such as phosphorous or boron within these nanostructures. We present in this study the elaboration, the structural and optical properties of SiO1.5 thin films doped with boron. The alloys were prepared by co-evaporation of SiO and SiO2 from two electron-beam guns in an ultrahigh vacuum chamber. Boron was supplied by a Knudsen cell for the low contents and from an electron beam gun for the high contents. The films were annealed at different temperatures until 1100°C in order to obtain the dismutation of SiO1.5 which results in Si NCs embedded in a SiO2 matrix. The structural and optical properties were studied by transmission electron microscopy (TEM), Fourier transform infrared absorption spectrometry and by photoluminescence (PL) experiments. Si NCs are observed by TEM in the annealed samples. Infrared absorption spectrometry allows us to follow the dismutation process and to observe an absorption band at 1380 cm-1 attributed to the O-B bonds. For low annealing temperatures, the PL spectra show bands attributed to defects. For annealing temperatures greater than 700°C, a band attributed to the Si NCs appears near 800 cm-1. This band disappears for high boron contents.

Authors : Angelo Monguzzi
Affiliations : Università degli Studi Milano Bicocca Department of Materials Science

Resume : Metal-organic frameworks (MOFs) are hybrid materials built up from organic molecules coordinated to metal ions or clusters. They have been originally developed for their tunable porosity interesting for industrial applications such as gas storing and sensing. Conversely, the research on luminescent MOFs nanocrystals is still at the early stage. The peculiarity of these nanocrystals is the possibility to pack chromophores close enough to allow a fast exciton diffusion, but sufficiently far from to preserve the electronic properties of an isolated ligands. However, most of the MOFs nanocrystals synthesized showed poor fluorescence quantum yield. Here, we realize a MOF nanocomposite with an unprecedented photoluminescence emission efficiency of 70% by a proper passivation of nanocrystal surface in a polymeric host. Moreover, we show how the confinement of triplets pairs in small MOF nanocrystals can enable a triplet-triplet annihilation yield of 100% regardless the excitation conditions, thus generating efficiently upconverted fluorescence. Using a rubber polymer doped with triplet sensitizers, we fabricated an upconverting nanocomposite working at subsolar irradiance. Our results demonstrate that the photophysical properties of these nano-structures, similarly to colloidal semiconductor quantum dots, are dominated by surface states and demonstrate a practical methodology to realize highly luminescent and industrially processable nanocomposites for photonic applications.

15:45 coffee break    
Authors : Leyre Gomez, Chris de Weerd, and Tom Gregorkiewicz
Affiliations : Van der Waals-Zeeman Institute, University of Amsterdam, The Netherlands

Resume : All-inorganic cesium lead halide perovskite nanocrystals (CsPbX3 NCs, X = Cl, Br, I) attract much attention due to their high photoluminescence quantum yields and narrow emission bands with wide tunability. They combine the advantages of perovskites and quantum dots creating an exceptional material for low-cost optoelectronic and photovoltaics. Conducting low-voltage electron energy loss spectroscopy on individual NCs, we provide novel insights regarding three important aspects of their microscopic behavior: (i) we explicitly demonstrate the relation between NC size and shape with their bandgap, and that the effective coupling between proximal NCs causes band structure modifications [1]; (ii) the synthesis of CsPbX3 NCs inevitably yields simultaneous formation of other nanostructures, insulating Cs4PbBr6 nanohexagons and hybrid nanospheres [2]; and (iii) drop-casted NCs merge spontaneously at room conditions by seamless stitching of aligned NCs, it can be accelerated by humidity and mild-temperature treatments, while arrested with electron beam irradiation [3]. Further, by using high-resolution induced absorption and emission spectroscopies, we obtain detailed information on carrier dynamics in perovskite NCs [4], their water-resistant encapsulation [5], and on energy exchange within their ensembles [6]. Finally, we discuss the most recent results on efficient carrier multiplication in CsPbI3 NCs [7]. [1] J. Lin et al. Nano Lett. (2016) [2] C. de Weerd et al. J. Phys. Chem. C (2017) [3] L. Gomez et al. ACS Applied Materials & Interfaces (2018) [4] E. M. L. D. de Jong et al. J. Phys. Chem. C (2017) [5] L. Gomez et al. Nanoscale (2017) [6] C. de Weerd et al. J. Phys. Chem. C (2016) [7] C. de Weerd et al. Nature Communications (2018)

Transport, Electronics : Caroline Bonafos
Authors : L.D.N. Mouafo 1, F. Godel 2, G. Melinte 1, S. Hajjar-Garreau 3, B. Dlubak 2, D. Halley1, Y. Henry1, O. Ersen 1, B. Doudin 1, L. Simon 3, P. Seneor 2, J.-F. Dayen * 1.
Affiliations : 1. Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504, F-67000 Strasbourg. 2. Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau. 3. Institut de Sciences des Matériaux de Mulhouse, CNRS-UMR 7361, Université de Haute Alsace, 3Bis, rue Alfred Werner, Mulhouse 68093.

Resume : We report a simple and scalable fabrication route of a new 2D material/ 0D clusters heterostructures, exploiting the self-organized growth over 2D material (graphene, or transition metal dichalcogenide) of epitaxial flat core-shell Al based nanoclusters assemblies.[1] Once implemented into into tunnel junctions, our 2D-0D heterostructures demonstrate well-defined robust and reproducible Coulomb blockade oscillations. Interestingly, these single electron features are preserved on devices with record contact areas of 100 µm² while such transport signatures are usually limited to nanoscale patterned devices in the 100 nm2 range. Finally, we unveil for the first time the spintronics properties of 2D-0D heterostructures, opening new avenues for 2D material spintronics.[2] Referencies : [1] F. Godel et al., Advanced Materials, 29, 1604837 (2017) [2] L.D.N. Mouafo et al., Advanced Materials, 30, 1802478 (2018)

Authors : Giacomo Torrisi, Melanie Micali, Antonio Terrasi
Affiliations : University of Catania - Cnr IMM ; University of Catania; University of Catania - Cnr IMM;

Resume : Transparent electrodes (TE) are critical materials for many devices in strategic technological areas such as photovoltaics (PV) and flexible electronics. In the case of thin film PV, the thickness of the TE must be reduced with respect to standard bulk solar cells, this being a big issue in terms of electrical and optical properties. The need of simultaneously good electrical, optical and structural properties for TE pushes to study new materials with respect to the standard TCOs (transparent conductive oxides) largely employed today, often containing expensive and toxic elements such as In. In this work we present experimental results on SiO2/Ag/SiO2 multilayer structures. The presence of the Ag intralayer and the very low thickness (only a few tens of nm) of this material produces very good electrical and optical properties (Rsh = 10 ?/? and ). In alternative to the TCO/Ag/TCO structure, the presence of the SiO2 can also a guarantee a good passivation of the interfaces. The quality and robustness of the SiO2/Ag/SiO2 has been investigated also in the case of depositions onto plastic substrates used for mechanical bending tests. In some cases, specific thermal annealing processes have been exploited to induce a partial de-wetting of the Ag film after sputtering deposition, in order to obtain a sort of Ag grid made of interconnected Ag islands. Samples have been characterized by UV-VIS-NIR spectrophotometry, 4-points electrical probe, RBS and SEM. Computer simulations have been performed to better understand the behavior of these structure and their potential applications. Our results suggest that SiO2/Ag/SiO2 can be successfully employed in several fields where ultrathin TE are critical materials.

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Sensing : Vincenzo Giannini
Authors : R. Gillibert and P. G. Gucciardi
Affiliations : CNR IPCF - Messina (Italy)

Resume : Polarization-sensitive Surface Enhanced Raman Scattering (PS-SERS) experiments are key for a full understanding of the SERS re-radiation enhancement from anysotropic nanoantennas and nanoantenna gratings. PS-SERS is also viewed as a potential tool for probing the Raman polarizability tensor at the single molecule level and/or the orientation of molecules absorbed on metal nanostructures. In this review talk we will provide a summary of the state of the art of the last 15 years experimental findings, together with new results highlighting the intriguing wavelength-dependent polarization rotation properties of gold nanorods arrays and nanoclocks.

Authors : Mario Urso 1, Salvatore Gianluca Leonardi 2, Nicola Donato 2, Giovanni Neri 2, Salvatore Petralia 3, Sabrina Conoci 3, Francesco Priolo 1, Salvo Mirabella 1
Affiliations : 1 MATIS CNR-IMM and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania, Italy; 2 Dipartimento di Ingegneria, Università di Messina, Contrada Di Dio, 98166 Messina, Italy; 3 STMicroelectronics, Stradale Primosole 50, 95121 Catania, Italy.

Resume : Gas sensing is receiving increasing attention driven by the need to ensure human safety by monitoring pollutant gases in the atmosphere such as NO2. Gas sensors based on metal oxides operating at room temperature are of great interest due to their energy saving and cost effective characteristics. Among the different materials investigated so far there is NiO, even if there are only a few reports regarding the low-cost fabrication of high-performance NiO-based sensors. In this work, we designed and fabricated a novel NiO nanofoam by a low-cost approach and applied it for the detection of NO2 at room temperature [1]. Ni(OH)2 nanowalls were directly synthesized onto interdigitated contacts by chemical bath deposition and converted into a 3D network of NiO nanoparticles (30-50 nm in size) through thermal annealing. Sensing tests showed a high response to NO2 at room temperature even for the lowest concentration of 140 ppb. In addition, the sensor presented an excellent selectivity at room temperature vs high concentrations of acetone, methane, CO, CO2, H2. The unique characteristics of the NiO nanofoam make it a potential candidate also for other applications such as electrochemical (bio)sensing, catalysis, energy storage. [1] M. Urso et al. Submitted.

Authors : Lucio Litti, Moreno Meneghetti
Affiliations : Department of Chemical Sciences, University of Padova, via Marzolo 1, Padova, Italy

Resume : The plasmonic properties of Au nanoparticles are nowadays well established along several sensor technologies. The Surface Enhanced Raman Scattering effect is just one of the examples, but has the peculiarity to be used as a characterization spectroscopy,[1] for contrast agents detection [2-4] or as a quantitative analytical tool.[5] One of the most important pre-requisite about an efficient SERS substrate, is that it should present as much as possible allowable hot spots, that are commonly tips or junctions with enhanced local fields. For this reason, large efforts were done on shape nano-gold in many different ways, but clustered gold nanospheres still seems to remain the best choice in terms of effort needed versus SERS efficiencies. Nevertheless, their intrinsically irregularity makes people skeptical about their usage. It is our believing that it could be solved by a better understanding about the role played by the hot spots on such irregular nanostructures and how all the surfaces contribute to the overall SERS enhancement factor. A model based on Boundary Element Method simulations is proposes as a versatile tool to interpret experimental extinction spectra of aggregated gold nanoparticles and to accurately predict the overall colloidal SERS EF. 1 G. Sciutto Analytica chimica acta 991 (2017) 2 F. Bertorelle Nanoscale 10 (2018) 3 F. Biscaglia Advanced Healthcare Materials (2017) 4 L. Litti Nanoscale 10 (2018) 5 L. Litti Journal of colloid and interface science 533 (2019)

Authors : G. Lucchini 1, P. Cortelletti 1, L. Rolla 1, L. Marciniak 2, D. Hreniak 2, A. Skripka 3, F. Vetrone 3, A. Speghini 1
Affiliations : 1 Nanomaterials Research Group, Department of Biotechnology and INSTM, Unità di Verona,Università di Verona, Strada le Grazie 15, Verona, Italia; 2 Institute of Low Temperatures and Structural Research, Polish Academy of Science, 50-422 Wroclaw, Poland; 3 Institut National de la Recherche Scientifique - Energie, Materiaux et Telecommunications (INRS - EMT), Universite du Quebec, 1650 Boul. Lionel-Boulet, Varennes, QC, J3X 1S2, Canada.

Resume : Lanthanide doped fluoride-based nanoparticles are very interesting for their possible use in modern technological applications, in particular as diagnostic probes in nanomedicine. In this presentation, we focus on binary (e.g. CaF2 or SrF2) and ternary (e.g. KY3F10) fluoride nanoparticles, activated with lanthanide ions (such as Yb3+, Nd3+, Tm3+, Er3+), prepared by hydrothermal synthesis1-2. Near infrared laser excitation at 980 nm or 800 nm of the nanoparticles can excite the lanthanides and induce strong emissions in the ultraviolet, visible and near infrared range. The variation of the emission intensities with temperature give rise to interesting thermometric properties of the nanomaterials. In particular, the thermal sensitivity and resolution can be evaluated by a ratiometric approach using emissions in different optical ranges. The nanoparticles under investigation show high sensitivities in the biological windows. A core@shell architecture of the nanofluorides is also considered to enhance their emission efficiency and also the performance as nanothermometers. References 1. Cortelletti, P.; Skripka, A.; Facciotti, C.; Pedroni, M.; Caputo, G.; Pinna, N.; Quintanilla, M.; Benayas, A.; Vetrone, F.; Speghini, A., Tuning the sensitivity of lanthanide-activated NIR nanothermometers in the biological windows. Nanoscale 2018, 10 (5), 2568-2576. 2. Pedroni, M.; Cortelletti, P.; Cantarelli, I. X.; Pinna, N.; Canton, P.; Quintanilla, M.; Vetrone, F.; Speghini, A., Colloidal nanothermometers based on neodymium doped alkaline-earth fluorides in the first and second biological windows. Sensor Actuat B-Chem 2017, 250, 147-155.

10:45 coffee break    
Authors : Franziska Barho, Fernando Gonzalez-Posada Flores, Laurent Cerutti, Thierry Taliercio
Affiliations : Univ Montpellier, CNRS, IES, UMR 5214, F-34000 Montpellier, France

Resume : Surface-enhanced spectroscopy techniques using plasmonic nanoantenna- or metasurfaces help to reduce the detection limit for biochemical sensing. While infrared spectroscopy is an excellent tool to identify a molecular species, a typically expensive IR light source is needed. We propose a spectroscopy technique based on the thermal emission of III-V semiconductor metasurfaces. The all-semiconductor metamaterial thermal emitter serves as a radiation source. A molecular layer grafted on the surface modulates the emission spectrum analogously to the modulation achieved in surface enhanced infrared absorption spectroscopy (SEIRA). We obtained qualitatively equal sensitivities comparing SEIRA and thermal emission spectroscopy using a metamaterial perfect absorber or thermal emitter functionalized with a monolayer of a trimethoxysilane compound. The vibrational fingerprints of this monolayer are detected due to the electromagnetic field enhancement obtained with the plasmonic metasurface. We probe the molecular vibrations based on the difference of the emittance measurements of the functionalized and non-treated metamaterial thermal emitter. Experimental observations of the enhanced molecular emission were confirmed using rigorous coupling wavelength analysis simulations. In sum, the experimental setup proposed is reduced because the metasurface acts simultaneously as radiation source and sensor chip. This innovative approach, surface enhanced thermal emission spectroscopy (SETES), is appealing for miniaturization and integration of sensing devices.

Authors : M. Banchelli (1), C. Amicucci (1), D. Ciofini (1), I. Osticioli (1), G. Ghini (2), C. D?Andrea (1), M. De Angelis (1), S. Siano (1), R. Pini (1), P. Matteini (1)
Affiliations : (1) Istituto di Fisica Applicata Nello Carrara, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy (2) Cabro Spa via Setteponti 141, 52100 Arezzo, Italy

Resume : The elusive nature of the misfolded protein species and their molecular interactions in the neuronal system, which are involved in neurodegenerative disorders (Alzheimer?s, Parkinson?s, dementia with Lewy bodies, etc.), are among the failure causes of the clinical approaches in any diagnosis or treatment attempted so far. Thus current research is extensively devoting efforts in unravelling the basis of the disease onset including the formation mechanism of aberrant protein species and the extreme structural variability in their toxic intermediates. Surface enhanced Raman spectroscopy (SERS) is well recognized as a powerful tool in detecting biomolecular species present in traces in liquid environments including body fluids. This technique can reveal important structural features such as elements of secondary structures and exposed aminoacidic residues of proteins, which can play a primary role in ruling intra- and inter-molecular interactions in a neuronal environment. The aberrant interactions of toxic misfolded protein intermediates with neurons, specifically with the components of the neuronal membrane, eventually lead to neurodegeneration through a cascade of biochemical processes. In this work, plasmonic optofluidic platforms of differently shaped silver nanoparticles were designed and fabricated with the aim of setting up SERS systems for label-free direct detection and analysis of proteins and biomarkers associated with neurodegenerative diseases such as Alzheimer?s and Parkinson?s. Typically, silver nanocubes and nanowires were synthesized and assembled through controlled methods to build up 2D patterned nanostructures with intense SERS activity. By means of tunable dewetting processes inside a microwell or a confined drop evaporation over hydrophobic matrices, the interaction pathways between the SERS active area and the analyte can be addressed to enrich the hot spot regions of the system with the target molecules, in turn improving effectiveness and sensitivity. Beyond a sensible and reproducible detection of various model and real biomolecular species these SERS platforms allowed an accurate structural analysis of toxic oligomers of beta-amyloid, which are recognized among the main biomarkers of the Alzheimer?s disease. References: [1] M.Banchelli, C. Amicucci, E. Ruggiero, C. D?Andrea, M. Cottat, D. Ciofini, I. Osticioli, G. Ghini, S. Siano, R. Pini, M. de Angelis, P. Matteini, Submitted for publication, (2018). [2] M. Banchelli, M. de Angelis, C. D?Andrea, R. Pini, P. Matteini, Sci. Rep. 8, 1033, (2018). Acknowledgments: M.B., C.D?A., A., R.P. and P.M. acknowledge the European Community within the EuroNanoMed3 ERANET cofund (H2020) project ?Surface-enhanced Raman scattering with nanophotonic and biomedical amplifying systems for an early diagnosis of Alzheimer?s disease pathology SPEEDY? (ID 221) and the Tuscany Region within the FAR FAS 2014 line A- project "Development of biophotonic sensors for OGM determination in the environment SENSOGM"

Authors : Vardan Galstyan, Andrea Ponzoni, Iskandar Kholmanov, Marta M. Natile, Antonella Glisenti, Elisabetta Comini, Giorgio Sberveglieri
Affiliations : Vardan Galstyan; Elisabetta Comini; Giorgio Sberveglieri (Sensor Lab, Department of Information Engineering, University of Brescia, Via Valotti 9, 25133 Brescia, Italy). Andrea Ponzoni (CNR - National Institute of Optics (INO), Via Branze 45, 25123 Brescia, Italy). Iskandar Kholmanov (Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA). Marta M. Natile; Antonella Glisenti (CNR-Institute of Condensed Matter Chemistry and Technologies for Energy, Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35131 Padova, Italy).

Resume : Chemical sensors based on metal oxide nanomaterials are among the most used devices for the detection of gaseous compounds during the environmental, safety, health and food quality monitoring. Gas sensor technologies are still developing and have yet to reach their full potential in capabilities and usage. Therefore, the improvement of metal oxides? sensing properties remains a challenging issue for the fabrication of low power consumption and small size chemical sensors. Graphene oxide (GO) and reduced graphene oxide (RGO) have unique properties that can revolutionize performances of functional devices. Herein, we report the synthesis and gas sensing properties of a composite material based on RGO and TiO2 nanotubes. We obtained TiO2 nanotubes by electrochemical anodization. GO was produced from natural graphite using a modified Hummers method and was reduced through the thermal reduction procedure. The morphological, compositional and structural analysis of obtained materials were performed. We systematically investigated the gas-response dependence from RGO loading and its reduction degree, showing the occurrence of an optimal RGO concentration arising from the interplay of these two parameters. In addition, the obtained results showed that RGO sheets improve the charge transport through the TiO2 tubular arrays enhancing the conductance of sensing material. Meanwhile, a depletion layer is formed between the n-type TiO2 and RGO sheets which plays an essential role for the improvement of the material sensing response. The obtained results indicate that we have developed a novel efficient approach for the coupling of GO with the metal oxide nanomaterials to fabricate high performance gas sensors and other functional devices.

12:00 Lunch    
Carbon, Graphene : Fabrice Gourbilleau
Authors : Milla Suominen1,2, Pia Damlin2 and Carita Kvarnström2
Affiliations : 1University of Turku Graduate School (UTUGS): Doctoral Programme in Physical and Chemical Sciences 2Turku University Centre for Materials and Surfaces (MATSURF), Laboratory of Materials Chemistry and Chemical Analysis, University of Turku, FIN-20014 Turku, Finland

Resume : Composite materials have been fabricated by combining mechanically strong carbon nanomaterials with energy rich pseudo capacitive conducting polymers to obtain better supercapacitors. This work presents the ionic liquid assisted electrochemical fabrication and characterization of conducting polymer/reduced graphene oxide composite films. Electrochemical preparation offers possibility to prepare the materials directly on various substrates using easily controllable conditions. Ionic liquids used were choline bis(trifluoromethylsulfonylimide) [Choline][TFSI] and imidazolium based IL (1-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4]). As conducting polymers, poly(3,4-ethylenedioxythiophene) (PEDOT) and polyazulene (PAz) were applied. The materials were studied by cyclic voltammetry and electrochemical impedance spectroscopy. Our results show that the composite materials possess higher capacitances than neat polymer films in three-electrode configuration. The obtained composite films also exhibit excellent cycling stabilities retaining over 90 percent of their initial capacitance after 1200 cycles. In composite materials, the two components interact with each other in a unique manner. It is possible to probe these interactions by combining electrochemistry with spectroscopy in in situ spectroelectrochemical techniques which enable the simultaneous monitoring of the electrochemical properties and the changes in both chemical and electronic structure. Our work has also aimed at understanding these interactions by using two in situ spectroelectrochemical techniques: in situ FTIR and in situ UV-Vis spectroscopy.

Authors : Alessandro Fantoni, Vladan Stojkovic, Miguel Fernandes, Manuela Vieira, Elisabete C.B.A. Alegria, Ana P.C. Ribeiro, Ana Carvalho
Affiliations : ADEETC-ISEL-Instituto Politécnico de Lisboa, 1949-014 Lisbon, Portugal 2 CTS-UNINOVA, Caparica, Portugal ADEQ-ISEL-Instituto Politécnico de Lisboa, 1949-014 Lisbon, Portugal CQE-Instituto Superior Técnico, Universidade de Lisboa,1049-001 Lisbon, Portugal DEE-FCT-UNL , Caparica, Portugal

Resume : Graphene-based materials have been extensively explored in recent years as valuable candidates as the key material for novel structures in the field, among many other applications, of sensing devices. Reduced Graphene Oxide (rGO) is a type of chemically derived graphene, with equivalent optical properties but easier to be synthetized. This work reports a study about the applicability of rGO as a support for gold nanoparticles (AuNPs). AuNPs are prepared with an economic and eco-friendly method using phytochemicals present in tea extract at room temperature, while a modified Hummer?s method is used to synthesize rGO. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the AuNPs. The resulting AuNPs-rGO composites will be studied in terms of UV-Vis spectroscopy spectral light transmission and plasmonic resonance and evaluated as a possible sensing element for a photonic protein sensor device. The overall analysis is supported by simulation results, obtained with DDSCAT numerical software, about the LSPR effect in AuNPs-rGO.

Authors : Sharali Malik, Felicite M. Ruddock, Adam H. Dowling, Kevin Byrne,Wolfgang Schmitt, Ivan Khalakhan, Yoshihiro Nemoto, Hongxuan Guo, Lok Kumar Shrestha, Katsuhiko Ariga, Jonathan P. Hill
Affiliations : Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe, Germany; Department of Civil Engineering, Liverpool John Moores University, Liverpool, L3 3AF, UK; Materials Science Unit, , Dublin Dental University Hospital, TCD, Lincoln Place, Dublin 2, Ireland; School of Chemistry and CRANN Institute, University of Dublin, Trinity College, Dublin 2, Ireland; Department of Surface and Plasma Science, Charles University, Czech Republic; International Center for Materials Nanoarchitectonics (WPI-MANA), NIMS, Tsukuba, Japan; Department of Advanced Materials Science, University of Tokyo, Japan

Resume : Statistically, we chew around 800 times in an average meal; that?s almost a million times a year. We put our teeth under huge mechanical strain, and often require fillings to repair them. Fillings are typically made of a mixture of metals, such as copper, mercury, silver and tin, or composites of powdered glass and ceramic. Typical metal fillings can corrode and composite fillings (thus far) are not very strong; Graphene on the other hand is 200 times stronger than steel and doesn?t corrode, making it a prime new candidate for dental fillings. Graphene can, therefore, be used to make mechanically stronger composite-dental fillings which also do not corrode. Despite some challenges and the fact that carbon nanotubes-polymer composites are sometimes better in some particular performance, graphene-polymer composites may have wide applications in dentistry due to their outstanding properties and the availability of graphene in a large quantity and at low cost. One of the main problems, for patients, associated with dental-polymers is that of location. This stems from the fact they must be situated within the mouth and this proves to be an extremely demanding setting, where exposure to moisture, high temperatures, and abrasion from tooth brushes plus intake of food all have to be dealt with. These conditions can lead to complications such as mechanical failures which negate clinical success and over time mandates remedial work for restoration with associated cost and inconvenience. Graphene has potential applications in dental-polymer materials as it has the required mechanical properties as well as being biocompatible. Here we present new work into the application of graphene for the fabrication of potential dental-polymer materials.

Authors : Xianghui Zhang?, Emanuel Marschewski?, Paul Penner?, Thomas Weimann?, Peter Hinze?, André Beyer? , and Armin Gölzhäuser?
Affiliations : ? Physics of Supramolecular Systems and Surfaces, Bielefeld University, 33615 Bielefeld, Germany ? Physikalisch-Technische Bundesanstalt, 38116 Braunschweig, Germany

Resume : There is significant research effort focused on sustainable energy and technologies designed to improve energy efficiency. Along this line, the fabrication of environmentally friendly energy storage devices such as capacitors with high energy density is of great interest. We report on the fabrication of large-area all-carbon capacitors composed of multilayer stacks of carbon nanomembranes as dielectrics sandwiched between two carbon-based conducting electrodes. Carbon nanomembranes are prepared from aromatic self-assembled monolayers of phenylthiol homologues via electron irradiation. Two types of carbon-based electrode materials, (1) trilayer graphene made by chemical vapor deposition and mechanical stacking and (2) pyrolyzed graphitic carbon made by pyrolysis of cross-linked aromatic molecules, have been employed for this study. The capacitor area is defined by the width of electrode ribbons, and the separation between two electrodes is tuned by the number of CNM layers, with a precision of 1 nm. Working ACCs with an area of up to 1200 ?m^2 were successfully fabricated by a combination of bottom-up molecular self-assembly and top-down lithographic approaches. Then ACCs were characterized by Raman spectroscopy, helium ion microscopy, and impedance spectroscopy. A dielectric constant of 3.5 and an average capacitance density of 0.3 ?F/cm^2 were derived from the obtained capacitances. A dielectric strength of 3.2 MV/cm was determined for CNMs embedded in graphene electrodes with the interfacial capacitance being taken into account. These results show the potential of carbon nanomembranes to be used as dielectric components in next-generation environment-friendly carbon-based energy storage devices.

15:15 coffee break    
Authors : Amir Navidfar, Levent Trabzon
Affiliations : Faculty of Mechanical Engineering, Istanbul Technical University, Istanbul, Turkey; MEMS Research Center, Istanbul Technical University, Istanbul, Turkey;

Resume : Polyurethane (PU) foams are used in a widespread range of applications such as insulators and dielectric materials, but their applicability is limited due to their poor mechanical properties. It seems appealing to modify PUs using nanoparticles. One-dimensional carbon nanotubes (CNTs) and two dimensional graphene nanoplatelets (GNPs) owing to their unique properties can be used as hybrid nanofillers to form well dispersed three-dimensional networks, which can overcome the dispersion problem of single nanofillers. CNTs and GNPs have a self-assembling ability due to the ? ?? interaction, which could decrease aggregations, resulting in enhancing the contact area between nanofillers and the polymer matrix. Micromechanical modeling and mechanical properties of PU hybrid nanocomposite foams with MWCNTs and GNPs were studied by mean of tensile strength and modified Halpin?Tsai equation. Three types of GNPs with various flake sizes and specific surface areas (SSA) were used to study GNP types dependence on the synergistic effect of MWCNT/GNP hybrid nanofillers. The results exhibit an outstanding synergetic effect between MWCNTs and GNPs with a flake size of 1.5 ?m and a higher SSA, which tensile strength of PU was enhanced by 43% as compared to 19% for MWCNTs and 17% for GNPs at 0.25 wt%.

Authors : Aamna AlShehhi,Irfan Saadat,Faisal Al Marzooqi, Amal Al Ghaferi
Affiliations : Masdar Institute of science and technology, Khalifa University

Resume : Since 2004 when the graphene material had been discovered, the studies have been focused to use it in multiple applications because of its fascinating properties. There are many substrates used for graphene growth such as copper, nickel and then can be transferred to other substrates such as dielectrics; SiO2 and Al2O3 using the traditional method of exfoliation. Atomic Layer Deposition (ALD) tool is used for dielectric deposition with different thickness to ensure the uniformity of growth. This paper will represent the direct growth of graphene into dielectric (Al2O3) and how can various parameters affect in the graphene quality. Actually direct growth of graphene material to various substrates open the door for many applications and make it more flexible in terms of the uniformity of growth and other challenges that was faced during the traditional exfoliation process. On the other hand, commercial Anodic Alumina Oxide (AAO membrane) is used a base substrate as well for direct growth of graphene in this paper. This kind of membrane is considered as insulator with various pore sizes 20 ? 200 nm and thickness of 50um. Planer Tech CVD is used for this purpose of graphene growth with monitoring the pressure and temperature as well as the flow rate. All these parameters will impact directly into graphene quality in terms of conductivity and the representation of the graphene peaks. Raman Spectroscopy with 532-wavelength laser has been used in the peak analysis where the D-mode, appears at approximately 1350 cm-1, G-mode at 1452 cm-1 and 2D-mode at 2680 cm-1. Furthermore, the stupendous results conclude the growth impact by the mentioned parameters (P, T and flow rate), which were observed by utilizing different tools to prove the feasibility of results such as Atomic force microscopy (AFM). Conductive ?AFM mode has been used for electrical conductivity measurements, which is measured to be 1 nA for the growth process of 100 torr pressure, flow rate of 10 sccm and 1000C. Also, Scanning Electron Microscopy (SEM) is used for surface analysis and identifies the difference before and after the growth. The impact of manipulating between these parameters will be presented in the final paper with additional characterization.

Authors : Harish Kumar Choudhary, Suryasarathi Bose, Balaram Sahoo
Affiliations : Materials Research Centre, Indian Institute of Science, Bangalore, India 560012 Materials Engineering, Indian Institute of Science, Bangalore, India 560012

Resume : Over the last decade, the escalating number of electronic communication devices and the greater use of microwaves radiation in advanced navigation and domestic appliances have resulted in a corresponding growth in electromagnetic interference (EMI). This inference deteriorates the performance of neighboring electronic devices and also has adverse effect on human health. Therefore, microwave absorbing materials or radar absorbing materials (RAM) which can has high absorption coefficient are requisite to overcome this problem. These RAM are also used in stealth technology to manufacture the fighter aircraft with minimum radar cross-section. The tuning of both the permittivity and permeability of the materials is important to achieve the higher microwave absorption. In this work, the EMI shielding and microwave absorbers behavior of magnetic metal(Fe, Ni, Co) filled carbon nanotube(CNT) in in 2-18 GHz frequency range is investigated. The effect of synthesis parameters such as temperature and defect generation through nitrogen doping on the microwave complex permittivity and permeability are studied and their role in achieving high EMI shielding layer is explored. Our synthesized magnetic CNTs are showing ~99% of EM attenuation. This high EM attenuation is due to the presence of Ferromagnetic resonance loss of magnetic particles along with the high ohmic loss and dielectric relaxation through polarons and bipolarons from the conducting CNTs and graphic carbon. The magnetic nanoparticles with tuned coercivity and saturation can helps in better impedance matching and the ferromagnetic resonance loss from the magnetic nanoparticles absorb the magnetic counterpart of the EM waves.

Poster session 2 : Simona Boninelli
Authors : Pratyusha Bhowmick (1), Koushik Biswas (1,2), Sudipto Ghosh (1,2), Rasmita Biswal (2)
Affiliations : (1) School of Nanoscience and Technology, Indian Institute of Technology, Kharagpur ? 721302, India (2) Metallurgical and Materials Engineering Department, Indian Institute of Technology, Kharagpur ? 721302, India

Resume : We report the facile synthesis of potassium niobate (KNbO3) nanorods (NRs) and nanocubes (NCs) with an orthorhombic phase. The orthorhombic nanostructures were synthesized via a hydrothermal method using Nb2O5 as a precursor. Furthermore, we tried to perform a low temperature in-situ hydrothermal synthesis of amorphous carbon nanotubes (A-CNTs) and reduced graphene oxide (RGO) based KNbO3 nanocompsite without the aid of any binder. This work may contribute to the synthesis of materials with new structures and hence improve the properties of the materials for various applications. Through researching the effects of reaction temperature, the optimum condition to prepare the orthorhombic potassium niobate nanostructures was investigated. The morphological and structural evolution of crystalline KNbO3 was studied in detail using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), High-resolution transmission electron microscopy (HRTEM), Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscopy (AFM) and Raman techniques. The present synthetic strategy enables us to tune the morphologies and structures of the niobate products by controlling the reaction kinetics. The reaction temperature and time need to be carefully optimized to yield high purity products with the desired crystal phase. Such a structural evolution provides a marvelous opportunity for selecting the niobate products with the desired morphologies and structures through the kinetic control of the reaction. Thus, the current study is of significant importance in developing new functional materials by wet chemical processes. Apart from this, we also tried to investigate the effect of incorporation of RGO and A-CNTs into the alkaline niobate products and observe the discerning changes in electrical properties while carrying out the impedance analysis for evaluation of dielectric properties. Till date, there are no reports of the application of RGO and A-CNTs based niobate nanocomposites in pyroelectric/ piezoelectric energy harvesting. This work may contribute to the synthesis of nanomaterials with new crystalline structures and hence improve the properties of the materials for various energy harvesting and storage applications.

Authors : Kang Eun Lee, Teahoon Park, Youngseok Oh, Jung-Keun Yoo, Moon-Kwang Um
Affiliations : Korea Institute of Materials Science

Resume : Photochromic molecules are organic molecules that can be able to undergo reversible photo-isomerization between two stable states which exhibit different properties. It has been shown that polymer composites with high photochromic molecules concentration can be prepared by dissolving azobenzene and other photochromic molecules in polymers. So we presented the organic field effect transistor (OFET) device with azobenzene derivative/PMMA blending film as the dielectric layer for the ultra-violet photosensor application in the previous study. Recently, several groups have demonstrated that ion-gel based on a mixture of an ionic liquid and a polymer can be used as gate dielectrics to obtain high capacitance and charge mobility in OFET devices. It is important to obtain high value of photocurrent with low gate voltage for UV sensor application. To improve the performance of the OFET based UV sensor devices, we introduced the photochromic molecule and ion-gel blending film as the dielectric layer for the UV photosensor application. We fabricated the ion gel film based OFET devices with top-gate and top-contact type structure by simple method. The devices showed reversible photo-responses upon alternating irradiation with UV and visible light and also had an high photoresponsivity under UV light.

Authors : Clément Majorel, Peter R. Wiecha, Arnaud Arbouet, Aurélien Cuche, Vincent Paillard, Christian Girard
Affiliations : CEMES-CNRS, Université de Toulouse, 29 rue Jeanne Marvig, BP 94347, F-31055 Toulouse, France

Resume : Photonic nanostructures are powerful instruments for controlling light on a scale smaller than the wavelength. The interest of the nano-optics is centered on the control of the optical electric field, because the response of the materials to the magnetic fields with fast oscillations is extremely weak. Materials with a significant response to the magnetic field of electromagnetic radiation do not exist in nature. But nanostructures with specific shapes or arrangements can increase their interaction with the magnetic field. We present a theoretical and numerical model, based on mixed field susceptibilities, to describe the dynamics of magnetic or electric dipole emitters induced by non-magnetic nanostructures of arbitrary shape. We extend the theory of Agarwal susceptibilities by introducing a method giving the decay rate of a dipole magnetic transition in terms of mixed magnetic field susceptibilities. We probe the decay rate maps generated by the coupling of magnetic dipole transitions with dielectric nanostructures of complex shapes and compare them to the case of electric dipole emitters. A reversal of contrast has been observed between the electrical and magnetic cases. Moreover, we demonstrate the versatility of this technique by coupling it to an evolutionary optimization algorithm. This allows us to predict structural geometries that maximize the decay of magnetic transitions.

Authors : G. Munzi1, M. Agati2, M.A. El Khakani3, P. Castrucci4 S. Boninelli2
Affiliations : 1 CNR-IMM, Via Santa Sofia 64, 95123, Catania, Italy; 2CNR-IMM, Strada VIII, 5, 95121, Catania, Italy; 3Institut national de la recherche scientifique, Centre-Énergie, Matériaux et Télécommunications (INRS-EMT), 1650 Blvd. Lionel Boulet, Varennes QC-J3X 1S2, Canada; 4Dipartimento di Fisica, Università degli Studi di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133, Roma, Italia

Resume : New and smart materials are of crucial importance to improve environment quality, which is fundamental for health, wellness and life. In this work, Silicon nanostructures are proposed as a filtering material due to their high surface area. These are particular Si/SiO2 core/shell Silicon Nanowires (SiNWs) that originate from Si/SiO2 core/shell spheres acting as substrate. The structure has been studied by the combined use of Scanning and Transmission Electron Microscopy; these techniques allowed us to observe that SiNWs exhibit three kind of core/shell structures. Photoluminescence (PL) has been tested by excitation with a 405 nm laser. Furthermore, these nanostructures are non-toxic, recyclable and economic as they are a by-product of an industrial process. Tests show that these nanoparticles have the capability to decolor an aqueous solution of a commonly used organic cationic dye (methylene-blue). A probable application of these SiNWs is an integration with an already existing filtration system, such as a membrane, to enhance its filtration properties. As polymer materials are widely used for many applications, including membranes for separations, it is our intention for the future to study the dispersion of this nanofiller in a polymer matrix through a structural characterization.

Authors : L.-M. Lacroix1, P. Moritz1, T. Leichle2, G. Viau1
Affiliations : 1. Université de Toulouse, UMR 5215 INSA, CNRS, UPS, Laboratoire de Physique et Chimie des Nano-Objets, Toulouse, France 2. LAAS, Toulouse, France

Resume : The liquid phase processes are very useful for the synthesis of magnetic nanoparticles with tunable properties. In this communication we will focus on the growth cobalt based nanoparticles, their compaction into metamaterials and their final integration into devices. Our motivation is to develop new generation of permanent magnets relying on the shape anisotropy of high aspect ratio magnetic nanoparticles. Co NRs with a diameter in the range 10-30 nm and aspect ratio varying between 5 and 20 were synthesized by the polyol process [1]. Dense assemblies of Co NRs exhibiting a square M(H) loop and a magnetic volume fraction higher than 50% were prepared. Magnets with an energy product, (BH)max, of 65 and 165 kJ.m-3 at large and small scale, respectively, were obtained [2,3]. Micromagnets were for the first time successfully produced and integrated into Micro Electro Mechanical Systems using an innovative approach based on magnetophoresis, leading to an efficient electromagnetic actuation. [1] M. Pousthomis et al., Nano Research 2015, 8, 2231. [2] U. Sanyal et al., Chem. Mater. 2016, 28, 4982. [3] E. Anagnostopoulou et al., Nanoscale 2016, 8, 4020.

Authors : L. Borkovska1, A. Rachkov2, T. Kryshtab3
Affiliations : 1V. Lashkaryov Institute of Semiconductor Physics of the NAS of Ukraine, 45 Prospect Nauky, 03028 Kyiv, Ukraine. 2Institute of Molecular Biology and Genetics of NASU, 150 Zabolotnogo Str., 03680 Kyiv, Ukraine 3Instituto Politécnico Nacional ? ESFM, Av. IPN, Ed.9 U.P.A.L.M., 07738 Mexico D.F., Mexico

Resume : Luminescent semiconductor nanocrystals (NCs) based on II-VI and I-III-VI materials are characterized by intense photoluminescence (PL) band tunable over the whole visible spectral range that makes them well suited for different optoelectronic and biomedical applications. The latter put forward high requirements for their photostability and non-toxicity. The polymer coating is often used to meet these two. In the present study, the photostability of nano-composites comprising of polymer embedded with doped semiconductor NCs, have been studied. Cu and Ag doped colloidal CdSe and In2S3 NCs were synthesized in aqueous solution and transferred to polyvinyl alcohol (PVA) and gelatine. Formation of Cu(Ag)-In-S solid alloys was confirmed by optical methods. The films and aqueous colloidal solutions were irradiated for several hours at room and elevated temperatures with light causing band-to-band transitions in the NCs. It is found that irradiation of Ag-doped NCs in PVA results in the darkening of the films and decreasing in intensity of defect-related PL band. The same changes were observed for colloidal solution of Ag-doped NCs. The processes accelerated at elevated temperatures. The effect is ascribed to formation of some light-absorbing species from the residual Ag-related compounds, most probably the metallic silver. In contrast, all gelatine-based composites were found to be quite photostable indicating that gelatine is more suitable matrix for optoelectronic applications.

Authors : Teayeop Kim, Sunho Park, Jangho Kim, Kyunghoon Kim
Affiliations : School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Korea; Department of Rural and Biosystems Engineering, Chonnam National University, Gwangju 61186, Korea; Department of Rural and Biosystems Engineering, Chonnam National University, Gwangju 61186, Korea; School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Korea;

Resume : There are many approaches to fabricate suitable support layers to enhance osmotic water flux in forward osmosis (FO) membrane. Supporting materials in FO membrane structures are required to be porous, hydrophilic and less tortuous microstructures. Eggshell membrane, one of abundant wastes, has hydrophilic surface, highly porous and fibrous structure expected to be less tortuous. In this work, we fabricated eggshell composite membrane (ESC) applying eggshell membrane (ESM) as a support layer. The ESC membranes are simply fabricated by polyamide active layer deposition via interfacial polymerization. Also, graphene oxide was used as an additive to further improve functionality of ESC membrane. Finally, in lab scale osmosis tests, ESC membranes with low structural parameter (~138 µm) showed a considerable osmotic water flux up to 45 lm-2h-1 in FO mode using 2 M NaCl draw solution.

Authors : Z. Skanderi 1* Y. Bouzaher1 Ilhem. R. Kriba2 A. Djebaili1
Affiliations : Z. Skanderi 1*; Y. Bouzaher1, , Ilhem. R. Kriba2, A. Djebaili1 1 Laboratory of chemistry and environmental chemistry L.C.C.E - University of Batna 1- Algeria 2 Faculty of Material Sciences- Department of Chemistry - University of Batna 1- 05000- Algeria

Resume : In this study, we used quantum chemistry calculations in order to determine some kinetic parameters of the isomerization reaction of the substituted icosadeca-ene. The studied molecules are: (C17H20, C17H12F8, C17H12Cl8, C17H12Br8 and C17H12I8) Cis and Trans. One of the adopted ways to access these parameters (activation energy, rate constant, etc ...) is looking for the transition state that is based on the exploration of intermediaries during the passage of Cis-Trans isomerization process. The study of a ten molecules series gives the following results: * The trans conformer is more stable than the Cis. * The activation energy changes very greatly depending on the size and nature of the substituent according to the reaction profile. * The constants of the isomerization reaction rates are in the following order: kC17H20 >> k C17H12F8 >> k C17H12Cl8 >>k C17H12Br8 >> k C17H12I8. * The geometrical parameters vary considerably according to intermediate products The calculation methods are DFT (TD-B3LYP) and Ab-initio methods at STO-3G*. Keywords: substituted icosadeca-ene, kinetics; isomerisation, HF (AM1+PM6), DFT

Authors : Dukhyun Choi, Dongseob Kim
Affiliations : Department of Mechanical Engineering, Kyung Hee University, South Korea, Aircraft System Technology Group, Korea Institute of Industrial Technology(KITECH), South Korea

Resume : The oxidation of metal microparticles(MPs) in a polymer film yields a mesoporous highly-deformable composite polymer for enhancing performance and creating a gapless structure of triboelectric nanogenerators (TENGs). This is a one-step scalable synthesis for developing large-scale, cost-effective, and light-weight mesoporous polymer composites. We demonstrate mesoporous aluminum oxide (Al2O3) polydimethylsiloxane (PDMS) composites with a nano-flake structure on the surface of Al2O3 MPs in pores. The porosity of mesoporous Al2O3-PDMS films reaches 71.35% as the concentration of Al MPs increases to 15%. As a result, the film capacitance is enhanced 1.8 times, and TENG output performance is 6.67-times greater at 33.3 kPa and 4 Hz. The pressure sensitivity of 6.71 V/kPa and 0.18 A/kPa is determined under the pressure range of 5.5 ? 33.3 kPa. Based on these structures, we apply mesoporous Al2O3-PDMS film to a gapless TENG structure and obtain a linear pressure sensitivity of 1.00 V/kPa and 0.02 A/kPa, respectively. Finally, we demonstrate self-powered safety cushion sensors for monitoring human sitting position by using gapless TENGs, which are developed with a large-scale and highly-deformable mesoporous Al2O3-PDMS film with dimensions of 6 x 5 pixels (33 x 27 cm2).

Authors : Anurima De, Bhanu Bhusan Khatua*
Affiliations : Indian Institute of Technology Kharagpur West Bangal 721302 India

Resume : With the advent of new technologically advances in materials science and engineering, a lot of current attention have been focused on developing electronic equipment that employs the use of shielding materials for electromagnetic interference (EMI). In this respect, a lightweight, flexible and absorbing shielding material draws a significant attention in the EMI based research community. Here, we have fabricated a flexible and light weight composite based on poly (vinylidene fluoride) (PVDF), Co doped CeO2 and RGO. A simple solvothermal method has been followed for the synthesis of Co doped CeO2 / RGO (CCR) from cobalt nitrate, cerium nitrate and graphene oxide. The fabricated composite Co doped CeO2/RGO- PVDF (CCRP) having thickness of 2 mm showed an EMI shielding effectiveness (EMI SE) value of ~30 dB in extended Ku band region at 6 wt% CCR loading. The room temperature ferromagnetic behaviour Co in CCR nanoparticles plays a vital role to enhance the EMI shielding value of the composite. The homogeneous dispersion of CCR and addition of RGO in the PVDF matrix also enhances the EMI shielding value of the composite. Thus, the fabrication of nanocomposites opens up a new avenue for developing next-generation EMI shielding materials.

Authors : Sergejus Balciunas (1), Mantas Sime?nas (1), Diana Pavlovaite (1), Martynas Kinka (1), Fa-Kuen Shieh (2), Kevin C.-W Wu (3), Juras Banys (1), Robertas Grigalaitis (1)
Affiliations : (1) Faculty of Physics, Vilnius University, Sauletekio av. 9, LT-10222 Vilnius, Lithuania (2) Department of Chemistry, National Central University, Chung-Li 32001, Taiwan (3) Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan

Resume : Remarkable gas adsorption properties of zeolitic imidazolate frameworks (ZIFs) are believed to be tightly related to a flexible nature of organic linkers in these compounds. We present a low-frequency dielectric spectroscopy study of dynamic effects in a ZIF-90 hybrid compound. Experiments of dehydrated framework reveal slow motion of the imidazolate-2-carboxyaldehyde linker in the kilohertz frequency range. Measurements of hydrated compound indicate two additional dynamic processes related to the adsorbed water molecules. These processes are assigned to the proton conductivity and relaxation of the supercooled water confined within the pores of the framework. We also study linker dynamics of dehydrated ZIF-90 in vacuum and under different gas atmospheres, revealing that the linker motion is significantly hindered by the guest molecules. We observed a significantly lower barrier of linker movement in vacuum compared with linker dynamics in different gas atmospheres showing a tight relation between the framework motion and guest molecules.

Authors : Xun Zhou, Xue Liang, Andrew Shevshuk,* Alex Ivanov,* Joshua Edel*
Affiliations : Imperial College London

Resume : Detecting biomolecules with heightened sensitivity is fundamental to healthcare-related researches such as disease diagnosis and treatment. Single-molecule methods are required to ultimately enhance the sensitivity of the biosensing. Among the existing single-molecule techniques, one of the major challenges for nanopore sensing is that proteins and small molecules are hard to be detected by a conventional nanopore sensing platform. Herein, we report a novel nanopipette fabrication protocol, with a small sensing area and an estimated diameter of nanopore below 10 nm, which leads to a much slower single-molecule DNA translocation. This strategy enables enhanced sensitivity of the single-molecule sensing of nanopores via the better temporal and spatial resolution of the resulting signals. This fabrication method is more affordable, easier and more stable to achieve than traditional pore fabrication methods such as focused ion beams. This innovative method is expected to bring us a leap forward towards enhancing the sensitivity.

Authors : Lei Kan, Hao Wei,* and Ning Ma *
Affiliations : Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China.

Resume : Mechanoluminescent polymers have received arising attention in the research field of polymer science and material science in recent years. Anthracene compounds, which can photo-dimerize to form non-fluorescent dimers under 365 nm UV light irradiation and recover to the fluorescent monomers via heating or UV light of 254 nm, are good candidates of dynamic covalent systems for the research on mechanoluminescent polymeric materials. In this work, the anthracene tailored trifunctionalized polyurethane (PU) prepolymers were synthesized and these prepolymers could form crosslinked structures via the dimerization of anthracene groups under UV irradiation. The dimerizing-crosslinked polyurethanes without fluorescence showed good mechanical properties which could bearing external stress and strain. It was found that blue fluorescence was observed when these anthracene dimer crosslinked materials was pressed or scratched, indicating that the anthracene monomers were regenerated by mechanical attack chain scission of the dynamic dimer structure. 1H-NMR investigation confirmed the formation of anthracene monomers after the mechanical experiments and the process of the regeneration of the anthracene was simulated by finite element analysis. Furthermore, the average and total intensity of fluorescence increased with the increasing pressure applied on the PU materials, suggesting the formation of anthracene monomers was closely related to the external force. We hope that these anthracene dimer crosslinked PU materials could provide a new avenue for fluorescent mechanosensitive materials. (This paper is funded by the International Exchange Program of Harbin Engineering University for Innovation-oriented Talents Cultivation.)

Authors : Jong Hyuk Park
Affiliations : Korea Institute of Science and Technology

Resume : Polymer nanocomposites incorporating nanofillers have achieved a variety of functionalities including mechanical, chemical, thermal, and electrical properties. However, the fundamental problem in such composites, poor compatibility between polymers and nanofillers, has limited the development of functionalities. Here, we demonstrate a simple and effective approach to address this issue without using compatibilizers. The plasma-assisted mechanochemistry (PMC) process can easily form covalent bonds between polymers and nanofillers even in the solid state, providing excellent processability, cost effectiveness, and environmental friendliness. Moreover, the PMC process can be applicable to nanoparticles as well as even chemically less active materials. Polyamide 66 (PA66) and hexagonal boron nitride (h-BN) were compounded via the PMC process, which can enhance the interfacial affinity between PA66 and h-BN and promote the uniform dispersion of h-BN platelets in the composites. The resulting PA66/h-BN nanocomposites exhibited significantly improved mechanical properties and thermal conductivities. In particular, the degradation in tensile strength of the composites due to the high h-BN content was completely prevented by the PMC process and the thermal conductivities of the composites were over four times higher than those of conventional composites. Therefore, this approach can provide nanocomposites with improved functionalities, thus greatly extending their applications.

19:00 Graduate Student Award ceremony followed by the social event    
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08:00 Conclusion    
Organic Materials : Minna Hakkarainen and Ignazio Roppolo
Authors : Raphael Pfattner, Victor Lebedev, Elena Laukhina, Anna Crespi, Marta Mas-Torrent, Vladimir Laukhin, Concepció Rovira, Jaume Veciana
Affiliations : Institut de Ciéncia de Materials de Barcelona (ICMAB-CSIC) Campus UAB, 08193 Bellaterra (Spain) and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN) ICMAB-CSIC, 08193 Bellaterra (Spain)

Resume : Developing smart materials that respond to an external stimulus is of major interest in artificial sensing devices able to read information about the physical, chemical and/or biological changes produced in our environment. Additionally, if these materials can be integrated on flexible, transparent substrates, their appeal is greatly increased. It is well known that single crystals of molecular conductors, consisting of ion-radical salts (IRSs) typically based on tetrathiafulvalene (TTF) derivatives, exhibit striking conducting properties [1]. Such properties can be further tuned by choosing the nature of the IRSs enabling a high sensitivity towards strain, pressure, temperature or even contactless radiation; i.e. bolometers [2,3]. In the reported bilayer nanocomposite films, composed of conducting polycrystalline layers of hydroresistive sub-micron sized BEDT-TTF IRS crystals on top of a dielectric polymeric host matrix is possible to electrically monitor relative humidity in a stable and fully reversible fashion [4]. This sensor platform enables the combination of high electrical performance of single crystals with processing properties of polymers towards a simple, low-cost and highly sensitive platform for applications in robotics, biomedicine and human health care. [1] E. Laukhina, et al. Synth. Met., 102, 1785, 1999 [2] E. Laukhina, et al. Adv. Mater., 21, 1-5, 2009. [3] R. Pfattner, et al. Adv. Electr. Mater., 1, 1500090, 2015. [4] R. Pfattner et al. submitted, 2019

Authors : C. Mendes-Felipe(1,2), P. Costa(3,4), J.L. Vilas-Vilela(1,2), S. Lanceros-Mendes(1,5)
Affiliations : 1 BCMaterials, Basque Center for Materials, Applications and Nanostructures, UPV/EHU Science Park, E-48940 Leioa, Spain; 2 Macromolecular Chemistry Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, E-48940 Leioa, Spain; 3 Center/Department of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; 4 Institute for Polymers and Composites IPC, University of Minho, 4800-058 Guimarães, Portugal; 5 IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain

Resume : Dielectric polymer based composites with barium titanate nanoparticles (BaTiO3) are increasingly being developed for applications ranging from electronic packaging and embedded capacitors to energy storage and sensors, since these composites are processed at low range temperatures, are highly flexible, exhibit a low dielectric loss, relatively high dielectric constant and high dielectric strength. As for the polymer-based matrix of these composites, UV radiation-curable polymers are getting increasing relevance due to their suitability for printing and coating technologies. Further, they are environmentally-friendlier materials (no solvents are used) and require low energy for curing, when compared to other conventional heat curable products. Furthermore, this technique is fast, obtains better patterns and works at room temperature. Dielectric composites have been prepared by UV curing based on polyurethane acrylate photoactive resin and BaTiO3 filler. The influence of filler content and size on the thermal, mechanical and morphological properties will be presented and discussed. In addition, the most suitable processing conditions for tuning dielectric constant and dielectric losses will be presented as a function of filler size and content. Work supported by the Portuguese Foundation for Science and Technology (FCT) -UID/FIS/04650/2013, PTDC/EEISII/5582/2014 and SFRH/BPD/110914/2015, by the Basque Government Industry Department under the EKARTEK and HAZITEK program and by the Basque Government Education Department under project PIBA (PIBA-2018-06).

Authors : Alicja Stola?1, Ida Östergren1, Iwan Darmadi2, Christoph Langhammer2, Christian Müller1, Kasper Moth-Poulsen1
Affiliations : 1Dept. Chemistry and Chemical Engineering, Chalmers University of Technology, 2Dept. Physics, Chemical Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden.

Resume : Nanoparticles bearing Surface Plasmon (SPR) and Localized Surface Plasmon Resonance (LSPR) phenomena are excellent tools for novel concepts and technologies such as the creation of bio- and chemosensors, plasmonic lasers, optical metamaterials. However, there is a number of challenges related to the use of nanoplasmonic systems associated to stability, composition and the large-scale incorporation in real devices. To address the above, we have used wet-chemical synthesis of palladium based plasmonic nanoparticles with tunable optical properties, and implemented these into suitable polymer matrixes, in order to invent cheap, easy and robust 3D ? printed nanocomposites. The nanocomposites are applied for preparation of an optical fiber hydrogen sensor. In this project Pd NCs for H2 sensing have been synthesized and successfully implemented into a PMMA matrix resulting in a H2 active nanocomposite. Effectiveness toward H2 sensing of the nanocomposite was tested with the use of a prototype sensor device, which was able to show consistent and repeatable H2 sensing response. The synthesis of nanoparticles is mainly surfactant based and is associated with a series of disadvantages that need to be mitigated such as the disruption of H2 absorption onto the Pd surface. Therefore, the impact of the surfactant on Pd Nanoplasmonic Hydrogen Sensing was explored, and several removal strategies were tested.

Authors : R. A. Puglisi*, V. Lombardo1, S. Di Franco, L. D’Urso, S. Scalese, Antonio Terrasi1 and A. La Magna.
Affiliations : CNR Istituto per la Microelettronica e Microsistemi, Strada Ottava 5, Zona Industriale, 95121 Catania, Italy; 1Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, 95123, Catania, Italy

Resume : Free standing polymers hold significant promise in thermoelectric devices, sensors, fuel cells, as photoactive layers in solar cells and as barriers for drug permeability. Black and opaque polymers find use in the textile manufacturing, in the thermal insulation systems, as well as flexible photovoltaics. In most of these applications the bottleneck to an extensive exploitation is the manufacturability coupled to the material tribological and reliability properties. We propose an effective in-solution method based on direct acid addition to the liquid PEDOT:PSS, one of the most popular polymers. The obtained material is a black gel that can be used as it is, or deposited on the substrate or alternatively it can be peeled away becoming a free-standing, robust and flexible foil. Several types of supports have been successfully tested. Layers up to 30 microns of thickness have been deposited so far. In principle, due to the flexibility and robustness of the films, there should be no limits to the thickness that can be obtained.

Authors : Gen-Wen Hsieh, Shih-Rong Lin, Yan-Sheng Chen
Affiliations : Insititute of Lighting and Energy Photonics, College of Photonics, National Chiao Tung University

Resume : The sense of touch, which is one of the most phenomenal ways of receiving information, has led to a ubiquitous need for several emerging applications, such as touch screens, mobile communications, wearable electronics, prosthetic/robotic skins and virtual reality. Even so the development of highly sensitive pressure sensors dealing with low pressure values (i.e., < 10 kPa) still remains a challenge. Very Recently, we have conducted a promising approach for polymer capacitive pressure sensors by formation of a dielectric composite layer containing zinc oxide (ZnO) nanostructure and poly(methyl methacrylate) or polydimethylsiloxane. We hypothesize that a new type of dielectric composites obtained through the addition of stress-sensitive nanostructures into polymeric matrixes may result in enhanced responses in capacitance for highly sensitive pressure sensing. Measurement results show that the ZnO-polymer capacitive pressure sensors yield a significant enhancement in pressure sensitivity, by a factor of up to 23, with respect to pristine polymer sensors. Notably, an ultrasmall load of only 10 mg (~three sesame seeds) can be reliably recognized. This approach provides a simple, convenient, and low-cost method for tiny load sensing, revealing the potency and feasibility for flexible touching & sensing electronic skin applications.

Authors : Parisa Zeaiean Firouzabadi(a), Hajar Ghanbari(a), Nafiseh Mahmoudi(b), Seyed Mohammad Amin Haramshahi(c), Jafar Javadpour(a)
Affiliations : (a) Department of Metallurgy and Material Engineering, Iran University of Science and Technology, P.O. Box 163-16765, Tehran, Iran (b) Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Tehran, Iran (c) Department of Tissue Engineering and Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, P.O. Box 144961-4535, Tehran, Iran *

Resume : Nanofibers composed of polymer and clay have benefited from dual physical, mechanical, and biological properties of clay and flexible polymer. This work aims to prepare a bentonite-polymer nanocomposite based on expansive, inexpensive bentonite, polyvinyl alcohol, and bacterial cellulose polymer by electrospinning for wound dressing applications. The nanocomposite was synthesized using a solution intercalation technique, in which, the nano-bentonite concentration varied between 1-2 %wt. The effect of commercial and laboratory-synthesized nano-bentonite, also extract of the green walnut shell (EGWS) examined. The nanocomposites samples were characterized by scanning electron microscopy (SEM), Fourier transforms infrared (FTIR) spectroscopy. The contact angle measurement, tensile strength test, and STA analysis also were done on the prepared mat. SEM images showed that the addition of commercial nano-bentonite to the polymer, up to 2 wt %, reduces the average size of the polymer fibers, While, a sharp increase in tensile strength is measured to more than 15 MPa. Fourier transform infrared spectroscopy reveals the formation of hydrogen bonding between the nano-bentonite sheets and the polymer matrix. By the addition of synthetic nanoclay and more clearer, EGWS, a moderate elongation and strength are achieved. Hydrophilicity shows a decreasing trend up to 2 wt % of commercial nano-bentonite, however, in the laboratory-synthesized nano-bentonite was not significantly affected at all. Effects of extracts on the viability of cultured human adipose tissue-derived stem cell were quantitated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay (Sigma). Results of MTT assay showed that the sample containing 2 wt % of commercial nano- bentonite had less toxicity than other nanocomposite mats. Antibacterial activity of the mats was tested against both E. coli (gram-negative) and S. aureus (gram-positive) bacteria according to the agar diffusion test for 72 h, in which, the mats obtained by the addition of EGWS exhibited strong antimicrobial activity. Keywords: Nanocomposite, Bacterial Cellulose, Nano-bentonite, Electrospinning, PVA, Antibacterial test

11:15 Plenary session 2    
12:30 Lunch    
Authors : Marco Sangermano
Affiliations : Politecnico di Torino, Dipartimento di scienza Applicata e Tecnologia Duca dgeli Abruzzi 24, 10129, Torino, Italy

Resume : Humidity sensors are of great interest in many fields because humidity plays a crucial role in several processes. Nevertheless, their application is often limited by the expensive fabrication and the stiffness of the substrates usually employed. In this work, we fabricated novel UV-curable and flexible humidity sensors based on semi-interpenetrated polymer networks. They can be prepared either as self-standing sensors or applied on different bendable substrates. The fabrication consists of a simultaneous UV-curing of an insulating network (acrylic or epoxy) and photo-polymerization of conducting polypyrrole (PPy). The detection mechanism involves proton transfer on the PPy chains that can be macroscopically observed by electrical impedance variations. These devices showed promising humidity sensing properties from 20 to 97 % of relative humidity with a maximum response of about 180 % (for epoxy-PPy). Acrylic-PPy sensors exhibited also notable response. Although it was lower than the epoxy one, acrylic-PPy sensors showed a faster recovery time. The remarkable sensing capabilities of these sensors make them a valid alternative in many applications where printability and flexibility are required along with simple fabrication method consisting of one-step-synthesis.

Authors : G. Munzi1, M. Ussia1,2, G. Gorrasi3, P. Castrucci4, M. A. El Khakani5, S. Boninelli6
Affiliations : 1 CNR-IMM, Via Santa Sofia 64, 95123, Catania, Italy; 2 Department of Physics and Astronomy ?E. Maiorana?, University of Catania, via Santa Sofia 64, 95123, Catania, Italy; 3 Università di Salerno, Dipartimento di Ingegneria Industriale, Via Giovanni Paolo II, 132, 84084 Fisciano (SA) Italy; 4 Dipartimento di Fisica, Università degli Studi di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133, Roma, Italia; 5 Institut national de la recherche scientifique, Centre-Énergie, Matériaux et Télécommunications (INRS-EMT), 1650 Blvd. Lionel Boulet, Varennes QC-J3X 1S2, Canada; 6 CNR-IMM, Strada VIII, 5, 95121, Catania, Italy

Resume : Polymer nanocomposites constitute an emerging class of versatile materials where the inclusion of appropriate nanofillers is intended to enhance or modify the polymer matrix properties. Such nanocomposite materials are conceived for multiple applications, spanning from agile mechanical materials or devices to drug delivery systems to sensors. In this work, composite films are prepared using polyEthilene-co-Vinyl Acetate (EVA) as the polymer matrix, and both Silicon NanoStructures (SiNSs) and Multi Walled Carbon Nanotubes (MWCNTs) as nanofillers. The SiNSs are used to investigate the optoelectronic properties of the nanocomposite films while the MWCNTs are incorporated to improve their electrical conductivity. Two different processes are compared for the film preparation, namely solvent casting and ball milling of the powder followed by their film casting via hot-pressing. The structural, electrical and optical properties of the different nanocomposite films were systematically investigated as a function of the different SiNWs and MWCNTs loadings. In particular, the loading of 15% w/w MWCNTs improved the nanocomposite electrical conductivity of several orders of magnitude, making it highly conductive. In conclusion, our study demonstrates that the easy processing of polymers associated with the peculiar properties of Si based nanostructures and MWCNTs, could give rise to a variety of novel nanocomposites which can be exploited for future applications in optoelectronics.

Authors : Philip Schäfer; Andreas Huber
Affiliations : neaspec GmbH, Eglfinger Weg 2, 85540 Haar, Germany

Resume : Scattering-type Scanning Near-field Optical Microscopy (s-SNOM) is a scanning probe approach to optical microscopy and spectroscopy bypassing the ubiquitous diffraction limit of light to achieve a spatial resolution of 10 nm. s-SNOM combines the best of two worlds, the nano-scale spatial resolution of Atomic Force Microscopy (AFM) and the analytical power of optical spectroscopy. It employs the strong confinement of light at the apex of a sharp metallic AFM tip to create a nanoscale optical hot-spot. This can be exploited for any wavelength from the visible light to the THz-region. Analyzing the scattered light from the tip interferometrically enables the extraction of the complex dielectric function (absorption, reflectivity) of the sample directly below the tip and yields nanoscale resolved optical images simultaneous to topography. Illuminating with a broadband infrared laser and detecting the elastically scattered light interferometrically (nano-FTIR) allows chemical identification of different materials in a nanocomposite with 10 nm spatial resolution. Nano-size impurities in polymer structures can be clearly detected and determined. Furthermore, plasmon modes in waveguides can be mapped with amplitude and phase, local free charge carrier densities and mobilities can be determined and even nanoscale photocurrent maps can be acquired. At last, our s-SNOM can also be used for ultrafast pump-probe experiments with down to 10 fs temporal resolution for studying fast excitation relaxation dynamics.

Authors : M. Campione (1), I. Villa (2), C. Villa (3), Y. Torrente (3), A. Vedda (2), A. Monguzzi (2).
Affiliations : 1. Department of Earth and Environmental Sciences, Università degli Studi Milano Bicocca, Piazza della Scienza 4, 20126 Milan, Italy; 2. Department of Materials Science, Università degli Studi Milano Bicocca, via R. Cozzi 55, 20125 Milan, Italy; 3. Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca? Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, via F. Sforza 35, 20122 Milan, Italy

Resume : Photodynamic therapy (PDT) is an alternative tumor-ablative and function-sparing oncologic intervention. PDT involves three components: light, oxygen, and a phototosensitizer, which produces upon photoactivation reactive oxygenated species (ROS), or singlet oxygen (SO). These moieties are responsible for the cell-killing and therapeutic effects. Despite its proved efficiency, the use of PDT is actually limited to superficial and flat lesions, because of the tissue-penetration depth limit of visible photons required by conventional photosensitizers. A potential solution is the use of scintillating nanoparticles to activate the SO sensitizers. The large penetration depth of x-rays removes the limit for the application of PDT in deep tissues. Upon excitation by ionizing radiation, light is generated by the nanoparticles and activates the photosensitizers through energy transfer to produce SO.[1] The radiation and photodynamic therapies are therefore combined and occur simultaneously, leading to a more efficient tumor destruction. Here, it is shown how hybrid fluorescent nanotubes can serve as X-PDT agents for targeting and treatment of brain cancer. An ionic self-assembly strategy is used to functionalize the surface of synthetic chrysotile scintillating mineral nanotubes with efficient SO-sensitizer organic dyes. The dye fluorescence properties are preserved from the in vitro to the in vivo condition, and functionalized nanotubes show the ability to migrate across the blood brain barrier, thus reaching the brain tumor after injection.[2] Upon x-ray irradiation, the hybrid nanotubes work effectively as SO sensitizers inducing cellular death. Encouraging tests conducted on human-derived glioblastoma neurospheres highlight the potential of these multicomponent nanomaterials for brain cancer treatment. The simplicity of the synthesis route combined with their affinity with the in vivo condition strongly support their development as effective functional materials for broader application in the biomedical field. [1] H. Chen et al. Nano Lett. 2015, 15, 2249; [2] C. Villa et. al. Adv. Funct. Mater. 2018, 1707582.

15:00 coffee break    
Authors : Ilya Sychugov, Yuanyuan Li, Sergei Popov, Lena Vasileva, Lars Berglund
Affiliations : KTH - Royal Institute of Technology, Stockholm, Sweden

Resume : Transparent wood is a novel composite attracting attention due to potential expanding functionality of this traditional load-bearing material into the optical domain. Delignification of wood samples with subsequent refractive index matching polymer impregnation leads to transparent wood composites, where the cell wall structure of the original wood material is fully preserved [1]. The resulting composite is highly transparent, but also features a strong haze due to anisotropic scattering [2]. Preserved wood fiber structure introduces peculiar effects on the polarization degree of the propagating light [3]. This allows wood structure characterization with visible light in contrast to traditional x-rays. For the application part incorporation of active fluorescent components, such as quantum dots [4] or fluorescent dyes [5] was also investigated. Luminescent and lasing panels or furniture components made of these hybrid materials may find utilization in general lighting, visible light communication, and in other areas. [1] Y. Li, E. Vasileva, I. Sychugov, M. Yan, S. Popov, L. Berglund, Optically transparent wood: recent progress, opportunities and challenges, Adv. Opt. Mater., 6 (2018) 1800059. [2] E. Vasileva, H. Chen, Y. Li, I. Sychugov, M. Yan, L. Berglund, S. Popov, Light scattering by structurally anisotropic media: A benchmark with transparent wood, Adv. Opt. Mater., 6 (2018) 1800999. [3] E. Vasileva, A. Baitenov, H. Chen, Y. Li, I. Sychugov, M. Yan, L. Berglund, S. Popov, Effect of transparent wood on polarization degree of light, submitted, (2019). [4] Y. Li, S. Yu, J.G.C. Veinot, J. Linnros, L. Berglund, I. Sychugov, Luminescent Transparent Wood, Adv. Opt. Mater., 5 (2017). [5] E. Vasileva, Y. Li, I. Sychugov, M. Mensi, L. Berglund, S. Popov, Lasing from Organic Dye Molecules Embedded in Transparent Wood, Adv. Opt. Mater., 5 (2017).

Authors : Daniel A. Bellido-Aguilar, Shunli Zheng, Yinjuan Huang, Zhong Chen.
Affiliations : School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore.

Resume : Approximately 90% of the world`s epoxy production relies on the use of the compound bisphenol A (BA). However, BA is a compound derived from petroleum, which makes the epoxy resin industry not environmentally sustainable as persistent demand on BA will contribute to the global warning and contamination as the exploitation of petroleum continues. Therefore, new green alternatives to BA are necessary to start the development of an environmentally sustainable epoxy resin industry. The focus of this research is to develop bio-based coatings with hydrophobic properties for anti-corrosion, anti-icing and easy cleaning applications. Two kinds of bio-based epoxy resins obtained from the oil of the cashew nutshell were utilized, together with two bio-based curing agents. The hydrophobicity of the bio-based coatings was achieved by the use of a fluorine-free additive. The thermal, mechanical and wettability properties of the bio-based thermosets were measured and the relationship with the kind of epoxy-curing agent formulation was analyzed and discussed. The anti-corrosion and anti-icing performances of the bio-based coatings were also evaluated and related to their wettability properties. Keywords: cardanol; bio-based; epoxy resin coating; hydrophobic; anti-corrosion;

Authors : A. Pikulin, N. Sapogova, A. A. Smirnov, N. Bityurin
Affiliations : Institute of Applied Physics RAS, 46 Ul'yanov Street, 603950, Nizhny Novgorod, Russia

Resume : Nanoparticles can be instantly generated in polymer matrices where the certain precursors are dissolved. The irradiation by light causes the photodestruction of the precursor molecules and formation of some kind of elementary species (such as atoms of gold) that further precipitate into the nanoparticles. The precipitation process is sensitive to the inpurities and inhomogeneities [N. Sapogova et al., Phys. Chem. Chem. Phys. 18, 32921?32930 (2016)] of the matrix. Utilization of segregated block copolymers as matrices can provide periodical inhomogeneities in a controllable way. In this work we perform the numerical modeling of the precipitation process of metal atoms in segregated matrices. We show that generation of nanoparticles in those matrices can lead to the fabrication of novel type of plasmonic metamaterials with deep spatial modulation of optical properties. This work was supported by the Russian Science Foundation (RSF) under project No. 18-79-10262.

Authors : Junzhi Li, Haoran Sun, Min Wang *
Affiliations : Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong * Email:

Resume : Bicontinuous interfacially jammed emulsion gels (?bijels?) are attractive due to their large interfacial area and interconnected channels for potential applications. Bijels can be used as templates to produce bicontinuous structures. For example, bijels-derived structures may form new hybrid solid electrolytes that consist of a continuous conducting phase and a continuous insulating phase. These electrolytes can have high conductivity. A major obstacle for wide applications of bijels and bijels-derived structures is difficulties in making bijels. In this study, a new method that can make large-size 3D bijels was developed. A ternary liquid mixture was made first by adding ethanol, diethylphthalate (DEP), deionized water, Ludox TMA and CTAB in ethanol. It was stirred vigorously and then stood for 12 hours to firm bijels. Confocal microscopy revealed the bicontinuous structure of bijels, which could be maintained for over 30 days at room temperature. By varying CTAB concentration, the domain size of bijels was changed. To explore the technique, we used hexanedioldiacrylate (HDA) and photo-initiator to replace DEP to generate solid structures. For HDA-based bijels, a UV light was applied to cure HDA. Freeze-drying then evaporated aqueous phase. The bicontinuous structure was clearly seen under SEM and interconnected channels were present. The new bijels fabrication method can lead to large exploration of bijels and bijels-derived structures for many applications.

16:15 coffee break    
Additive Manufacturing : Marco Sangermano
Authors : Ignazio Roppolo
Affiliations : Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy

Resume : In the last years, 3D Printing (3DP) is increasing its importance both in science and in industrial applications due to the peculiar properties and manifolds advantages that the technologies that are included under this umbrella terms can offer.[1] Without going into details for each technology, it is implied the possibility to produce components with shapes impossible to obtain by classical subtractive manufacturing, saving at the same time both raw materials and energy.[2, 3]. Among polymeric 3D printing processes, light-based technologies (SLA and DLP) are generally known for being the fastest and most precise. However their main drawback consists in the limited palette of available printable materials, which restrict the possible applications. Aiming to widen the range of printable materials for DLP, here we will show different strategies for producing 3D printable nanocomposites developed in our laboratories. The idea beyond consists in imparting improved mechanical properties or new functionalities to the printed objects maintaining at the same time a good printability. In this context we will show that a classical direct dispersion of fillers in a photocurable formulation followed by the optimization of printing parameters ( what we call ?the materials? engineering approach?)[4, 5] could be overcome by an appropriate design of the photocurable mixture, adding a bit of materials? science and chemistry. This allows to obtain objects with peculiar properties saving a high printability.[6-8] References: 1. T.A. Campbell, O.S. Ivanova, 3D printing of multifunctional nanocomposites, Nano Today, 2013, Vol. 8, 119-120. 2. F.P.W. Melchels, J. Feijen, D.W. Grijpma, A review on stereolithography and its applications in biomedical engineering, Biomaterials, 2010, Vol. 31, 6121-6130. 3. R.D. Farahani, M. Dubé, D. Therriault, Three-Dimensional printing of multifunctional nanocomposites: manufacturing techniques and applications, Advanced Materials, 2016, Vol. 28, 5794-5821. 4. G. Gonzalez, A. Chiappone, I. Roppolo, E Fantino, V. Bertana, F. Perrucci, L. Scaltrito, F. Pirri, M. Sangermano; Development of 3D printable formulations containing CNT with enhanced electrical properties, Polymer, 2017, vol. 109, pp. 246-253 5. A. Chiappone, I. Roppolo, E. Naretto, E. Fantino, F. Calignano, M. Sangermano, C.F. Pirri; Study of graphene oxide-based 3D printable composites: Effect of the in situ reduction, Composite Part B: Engineering, 2017, Vol 124, pp 9-15. 6 J.Wang, A. Chiappone, I. Roppolo,F. Shao, E. Fantino, M. Lorusso, D. Rentsch, K. Dietliker, C.F. Pirri, H. Grützmacher; All-in-One Cellulose Nanocrystals for 3D Printing of Nanocomposite Hydrogels, Angewandte Chemie International Edition, 2018, vol 57, pp 2353-2356 7 E. Fantino, A. Chiappone, I. Roppolo, D. Manfredi, R.M. Bongiovanni, C. Pirri, F. Calignano; 3D Printing of Conductive Complex Structures with In Situ Generation of Silver Nanoparticles. Advanced Materials 2016, vol. 28, pp. 3712-3717 8. A. Chiappone, E. Fantino, I. Roppolo, M. Lorusso, D. Manfredi, P. Fino, C. Pirri, F. Calignano; 3D Printed PEG-Based Hybrid Nanocomposites Obtained by Sol?Gel Technique. ACS Applied Materials & Interfaces Vol. 8, pp. 5627-5633

Authors : Ida Östergren 1, Alicja Stolas 1, Iwan Darmadi 2, Kasper Moth-Poulsen 1, Christian Müller 1 and Christoph Langhammer 2
Affiliations : 1, Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 412 96 Göteborg, Sweden 2, Department of Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden

Resume : Plasmonic nanoparticles have intriguing properties that can be used as building blocks for optical metamaterials, in photocatalysis, for medical treatments and sensing applications. To fabricate devices based on plasmonic nanoparticles methods such as nanolithography are widely employed, which unduly increases fabrication cost and stands in the way of a cost efficient and scalable technology. In this contribution I will present our efforts to process plasmonic devices in a radically different way. Specifically, we chose to embed gold or palladium nanoparticles, synthesized via wet-chemistry, in a thermoplastic polymer matrix, thus creating plastic-plasmonic hybrid materials. These composites can be readily extruded into filaments. 3D printing using fused filament fabrication, a widely used additive manufacturing technique, then allowed us to realize macroscopic plasmon-active objects with a large variety of shapes and architectures. Among them, we were able to fabricate 3D-printed optical plasmonic hydrogen sensors with remarkable response times, ranging from seconds to minutes depending on the dimensions and nanoparticle stoichiometry, and with intrinsic resistance towards deactivation of carbon monoxide. Evidently, 3D printing is a viable approach for fabrication of more cost-efficient and scalable plasmonic devices.

Authors : Simone Lantean1,2, Ignazio Roppolo1, Marco Sangermano1, Giancarlo Rizza2
Affiliations : 1Department of Applied Science and Technology (DISAT), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy 2Laboratoire des Solides Irradiés (LSI), Ecole Polytechnique, Université Paris-Saclay, Route de Saclay, 91128 Palaiseau Cedex, France

Resume : Recently, polymeric soft-actuators activated by magnetic fields are gaining more and more interest. By coupling flexible polymeric matrices and magnetization it is possible to fabricate objects which undergo large deformations under low applied forces, and their movements can be remotely controlled. Digital Light Processing (DLP), a photoinduced 3D printing technique looks very advantageous for the production of these devices. In fact, it is possible to take advantage of the fast polymerization kinetics of the photopolymerization, together with the easy dispersion of magnetic fillers in liquid resins, which can undergo to a self-assembly process when exposed to external magnetic fields. It is thus possible to build polymeric nano-composite materials where the magnetic self-assembled chains constitute the programmed hierarchal microstructures. In this work, we dispersed magnetite (Fe3O4) nanoparticles (NPs) in a urethane-acrylic formulation (Ebecryl 8232, Allnex) suitable for DLP process. The formulations were then exposed to external magnetic fields, investigating the evolution of the microstructure. Several parameters as magnetic field intensity, magnetization time, and system viscosity were studied in relation to the average length, and length-distribution of the formed Fe3O4 chains. The influence of a reactive diluent (BA) on the flexibility of the material was evaluated as well as the influence of Fe3O4 NPs in photopolymerization kinetics. Once defined the best conditions, formulations were 3D-printed by a DLP equipment: complex shape objects were produced, and their response to external magnetic stimuli was investigated, together with their mechanical and thermal characteristics.

Authors : Igor Shishkovsky, Vladimir Scherbakov
Affiliations : Skolkovo Institute of Science and Technology (IS); Lebedev Physics Institute of RAS (VS)

Resume : At present study, the possibility of controlling the morphology, shape and porosity of ceramic-polymer matrix (CPM) based on a polymer with the addition of nano titanium dioxide (TiO2) during powder bed fusion process was shown. We have experimentally determined the optimal regimes for layerwise laser melting. The 3D parts were obtained from polycarbonate + nano-titania powder compositions with 10: 1 and 5: 1 (by vol.) ratio. The geometric and microstructural features of the created 3D samples by the methods of linear measurements of transverse dimensions, optical microscopy (OM) and x-ray analysis were evaluated. The OM indicates a heterogeneous distribution of nano-titania in the polymer matrix. The XRD patterns showed the presence of the initial phase (TiO2) without significant changes, which is useful for plasmonic applications. Additional thermal heating near 30 min of 3D parts in the oven in the range of 150?400 degrees revealed conditions for changing the porosity of the CPM, removing the polymer binder and titania framework fixing. With the CPM porosity decrease, the diffusion coefficient of electrons in TiO2 increases, which leads to an increase in the density of the generated current and the efficiency of solar cells.

Authors : Hadis Khakbaz, Dr. Stephen Beirne, Prof. Peter C. Innis
Affiliations : ARC Centre of Excellence for Electromaterials Science, Intelligent Polymer Research Institute, Innovation Campus, University of Wollongong, North Wollongong, NSW 2500, Australia

Resume : 3D additive manufacturing has shown significant promise in fabricating customized complex structures for bioelectronic applications. Mechanical flexibility is a highly critical feature for bioelectronic devices which are in direct contact with biological tissues. Thermally conductive polymer nanocomposites with high cytocompatibility are required to meet the requirements of complex 3D architectures for use in bioelectronics. This study investigates the 3D printability of highly flexible, thermal conductive and biocompatible boron nitride (BN) thermoplastic polyurethane (PU) nanocomposites. BN nanoparticles, a ceramic additive with high thermal conductive and electrical insulating properties, were added to the PU in order to manage heat transfer. The BN-PU nanocomposites exhibited acceptable mechanical and highly thixotropic properties that make them as favorable candidates for extrusion-based 3D printing. Flexible structures of BN-PU nanocomposites were 3D printed using a pneumatic-based 3D printer. The thermal conductivity of nanocomposites was increased by more than 50% at loadings of up to 20 wt% of BN. This work demonstrates the potential applications of the BN-PU nanocomposite as a biocompatible material in bioelectronic devices.


No abstract for this day

Symposium organizers
1. Giancarlo RIZZA (Main Organizer)Laboratoire des Solides Irradiés (LSI) - Ecole polytechnique

Route de Saclay, 91128 Palaiseau Cedex, France

+33 (0)1 69 33 45 10

Strada VIII n.5, 95121 Catania, Italy

+39 349 1890259
3. Minna HAKKARAINENKTH Royal Institute of Technology

Fibre and Polymer Technology - School of Engineering Sciences in Chemistry, Biotechnology and Health, Teknikringen 56-58, 10044 Stockholm, Sweden

+46 (0)8 79 08 271
4. Domenico PACIFICIBrown University

School of Engineering, 184 Hope St, Providence RI 02906, USA

+1 401 863 2637