Materials and devices for energy and environment applicationsD
12th International Symposium on Electrochemical/ Chemical Reactivity of New Materials – „Surface Science – key to understand advanced materials”
Introduction and scope:
This Symposium is aimed at following the tradition already established by the previous Symposia in Warsaw (1993, 1996, 2003, 2007, 2010), Szeged (1995, 2005), Dresden (1997), Sendai (1998), Mt.Tremblant (2001) and Krakow (2012).
The symposia in 2007 and 2010 were held in Warsaw as a part of the European Materials Research Society (EMRS) - Fall Meetings in order to extend the (necessary) stimulating collaboration of chemists and physicists with material scientists. Since these events were very successful, the Scientific Committee of the cyclic Symposia has decided to continue with this Symposium to be held as one of the Symposia in E-MRS Fall Meeting 2015.
The scope of our Symposium belongs to the general topic “Surface Science – key to understand advanced materials” and is aimed at promoting various opportunities for interdisciplinary collaboration of scientists from around the world in addition to presentation of new results, ideas and technologies in the field of chemical, physical properties of novel materials including nanocrystalline, amorphous materials and various kind of thin films, coatings, layers and deposits obtained by chemical/electrochemical and physical methods.
Discussion among specialists from the areas of materials science, physics, chemistry and electrochemistry should contribute to:
- characterizing the critical factors controlling the chemical properties of novel amorphous and nanostructured materials,
- understanding of the chemical and electrochemical process for surface modification and activation of advanced materials to applications for catalysis, electrocatalysis, photoelectrocatalysis, energy conversion and storage and biomedical applications,
- finding efficient, interdisciplinary processes for tailoring novel functional materials,
- getting new insight into the chemical and electrochemical processes and mechanisms in catalysis and electrocatalysis,
- fabrication of functional amorphous and nanocrystalline oxide films by electrochemical oxidation of metals and alloys for energy conversion (fuel cells, solar cells and batteries) and also photocatalytic decomposition of pollutants.
Topics covered by the symposium:
- New perspective materials for catalysis and electrocatalysis
- Functional nanomaterials: properties, characterization and applications
- Chemical and electrochemical methods for surface functionalization: potential applications
- New materials in renewable energy production
- Solid state materials characterization - physical methods
- Vibrational spectroscopy in “Chemistry for Materials Science”
- Electron Spectroscopy – theory and practical applications
- New generation of biomaterials
Symposium opening lecture:
- Philippe Marcus, Institut de Recherche de Chimie Paris, France, title to be announced soon
- Andrzej Całka, Faculty of Engineering and Information Sciences, University Wollongong, Australia, Enhanced chemical reactivity of metallic and ceramic materials in plasma environment during Electric Discharge Assisted Mechanical Milling
- Neil Fox, School of Chemistry, University of Bristol, UK, Diamond Materials for Energy Conversion
- Georg Held, University of Reading, Reading, UK, Photoelectron spectroscopy under Near-Ambient-Pressure Conditions - Surface Science meets the real World
- Pavel Jelinek, Nanosurf Lab, Institute of Physics of the ASCR, Prague, Czech Republic, High resolution AFM/STM images of molecules with functionalized tips: experiment and theory
- Torben Rene Jensen, Department of Chemistry, Aarhus University, Aarhus, Denmark, Multi-functional Energy storage materials
- Gediminas Niaura, Center for Physical Sciences and Technology, Vilnius, Lithuania, Electrochemical SERS characterization of functional monolayers at metal surfaces
- Markus Niederberger, Laboratory for Multifunctional Materials, ETH Zürich, Switzerland, Controlled Synthesis and Assembly of Metal Oxide Nanoparticles over Several Length Scales
- Marek Nowicki, Institute of Experimental Physics, University of Wroclaw, Poland, Solid-Liquid Interfaces Investigated by EC-STM and CV
- Isao Saeki, Muroran Institute of Technology, Mechanical, Aerospace, and Materials Engineering, title to be announced shortly
- Bartosz Such, Faculty of Physics, Jagiellonian University, Krakow, Poland, SPM study of adsorption of porphyrin-based dyes on TiO2
- Grzegorz Sulka, Faculty of Chemistry, Jagiellonian Univeristy, Krakow, Poland, Anodic valve metal oxides - synthesis and applications
- Jolanta Światowska, Institut de Recherche de Chimie Paris, France, Contribution of surface spectroscopic techniques to characterization of materials for electrochemical energy storage and conversion systems
- Mikito Ueda, Faculty of Engineering, Materials Science and Engineering, Ecological Materials, Hokkaido University, Japan, Electrodeposition of Al alloys in non-aqueous liquid
- Robert A. Varin, Waterloo Institute for Nanotechnology, University of Waterloo, Canada, Mechano-chemically synthesized novel hydride nanocomposites for low temperature hydrogen generation
- Akiko Yamamoto, National Institute for Materials Science, Tsukuba, Japan, The effects of cells and other factors on biocorrosion of Mg and its alloys.
- Jan Augustyński, Faculty of Chemistry, Warsaw University, Warsaw, Poland, Plasmonic and electrocatalytic effects of metal nanoparticles in photoelectrochemistry
- Sebastian Fiechter, Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany, Hybrid Electrolyzers for Light Driven Water splitting - Materials for Photoelectrodes and Electrocatalysts
- Stanisław M. Filipek, Unipress Institute of High Pressure Physics of the Polish Academy of Sciences, Interaction of selected intermetallic compounds with hydrogen under high pressure conditions
- Koji Hashimoto, Institute for Materials Research, Tohoku University, Sendai, Japan, Renewable energy supply in the form of methane by conversion of carbon dioxide to methane via electrolytic hydrogen generation
- Paweł Kulesza, Faculty of Chemistry, University of Warsaw, Warsaw, Poland, Importance of specific interactions between support and active centers in efficient electrocatalysis and photoelectrocatalysis
- Arpad Molnar, Department of Chemistry, University of Szeged, Szeged, Hungary, Homeopathic Catalysis
- Klaus Wandelt, Institute of Physical and Theoretical Chemistry University of Bonn, Bonn, Germany, Metal/Electrolyte Interfaces: Atomic scale insights and control
Other confirmed lecturers:
- Christine Blanc, School of Chemical Sciences and Engineering, Toulouse, France, Corrosion and Stress Corrosion Cracking behaviour of metallic alloys in relation to local metallurgical state and grain boundary misorientation
- Saschiko Hiromoto, National Institute for Materials Science, Tsukuba, Japan, In vitro and in vivo degradation behaviour of calcium phosphate-coated bioabsorbable magnesium alloy
- Mohamed Jouini, University Paris‐Diderot Sorbonne‐Paris, France, In situ preparation and use of conducting polymers as hole transporting material in solid state dye sensitized solar cells
- Zenta Kato, Tohoku Institute of Technology, Sendai, Japan, Influence of the coating solution and calcination condition on the durability of Ir1-xSnxO2/Ti electrodes for oxygen evolution
- Tomasz Kobiela, Faculty of Chemistry, Warsaw University of Technology, A new procedure for efficient roughening of gold surfaces
- Jan Krajczewski, Faculty of Chemistry, University of Warsaw, Catalytic activity for ethanol electrooxidation of differently formed platinum layers
- Katarzyna Krupski, Department of Physics, University of Warwick, Structural Optimization Of Titanium Dioxide of (4×1) Reconstruction for Photocatalytic Applications
- Andrzej Kudelski, Faculty of Chemistry, University of Warsaw, Synthesis and characterisation of new types of nanoresonators for Raman analysis of surfaces
- Nazukao Kumagai, Hitachi Zosen Corporation, Kashiwa, Japan Production of Fuel from CO₂; Methanation with CO₂ and H2 Produced from Renewable Energy
- Małgorzata Lewandowska, Faculty of Materials Science and Engineering, Warsaw University of Technology, Corrosion resistance of nanostructured aluminium alloys - effect of grains boundaries and second phase particles
- Krzysztof Miecznikowski, Faculty of Chemistry, University of Warsaw, Electrocatalysts for Oxidating of Polyhydric and Monohydric Alcohols to Carbon Dioxide on Platinum Alloy Nanoparticles Dispersed on Noble Metal Oxides
- Ingrid Milosev, Institut "Jožef Stefan", Ljubljana, Slovenija, Corrosion protection of aluminium alloys by hybrid coatings as alternative to chromate protection
- Monica Santamaria, Dipartimento di Ingegneria Chimica dei Processi dei Materiali, Universita di Palermo, Italy, The Influence of Composition on Band Gap and Dielectric Constant of Anodic Al-Ta Mixed Oxides
- Wojciech Stępniowski, Faculty of Advanced Technologies and Chemistry, Military University of Technology, Incorporation of chelate anions, organic dyes and colloids into anodic aluminum oxide
- Hiroyuki Takano, Hitachi Zosen Corporation, Japan, Improved catalysts for carbon dioxide methanation
- Galina Tsirlina, Lomonosov Moscow State University, Russia, Electrodeposition of non-stoichiometric oxides as a tool to tune their functional properties
- Melvin Vopson, Department of Earth and Environmental Sciences, University of Portsmouth, Nano-multiferroic composites for magnetic data storage
- Piotr Żabiński, Department of non-ferrous metals, AGH University of Science and Technology, Tuning of catalitical activity for hydrogen evolution of electrodeposited cobalt alloys by superimposed magnetic field
The Selected papers will be published as a special issue of the journal Applied Surface Science. The format, letter type and lay out will be the same as for the regular issues of the Journal. There will be no page charges. On-line submission via Elsevier’s Editorial System (EES) at http://www.ees.elsevier.com/apsusc/ is required. Deadline for submission of manuscripts will be given later.
Co-organizers of the Symposium (institutions, companies):
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Authors : Pawel J. Kulesza, Iwona A. Rutkowska, Krzysztof Miecznikowski, Adam Lewera, Sylwia Zoladek, Renata Solarska, Anna Wadas, Ewelina Szaniawska
Affiliations : Faculty of Chemistry, University of Warsaw
Resume : The most commonly considered electrocatalytic systems (e.g. for oxygen reduction) utilize precious platinum and, therefore, there is a need to minimize contents of Pt. (e.g. by activating it with certain metal oxo-species including polyoxometallates of tungsten) as well as to look for alternate molecular catalysts comprising metalloporphyrins or N-chelates combined with Ru-based chalcogenides, and bifunctional materials inducing reduction of both oxygen and hydrogen peroxide intermediate. Broad utilization of hydrogen-oxygen fuel cells would require development of effective means of hydrogen production and storage. In this context, the visible-light induced photelectrocatalytic water splitting is an important concept that will be addressed in this presentation as well. The problem of oxygen reduction is even more severe in a case of alcohol-utilizing fuel cells. In this respect, heat-treated carbon-supported macrocyclic complexes and their derivatives as well as chalcogen modified transition metals are promising and selective (e.g. methanol tolerant) platinum-free catalysts. Our research interests also concern development of systems leading to the enhancement of the carbon dioxide reducytion. We can consider here supramacromolecular complexes of palladium, platinum and copper. Among important issues are specific interactions between nitrogen coordinating centers and electrogenerated metallic sites at the active interface. Some attention will also be paid to photoelectrochemical reduction at mixed semiconducting oxides (e.g. TiO2 and Cu2O) and to specific interactions between them. When it comes to electrocatalytic oxidation, the most common Pt anodes are readily poisoned by the strongly adsorbed intermediates, namely by CO-type species, requiring fairly high overpotentials for their removal. We have recently demonstrated that catalytic activity of platinum-based nanoparticles towards electrooxidation of ethanol, dimethyl ether or methanol has been significantly enhanced through interfacial modification with ultra-thin monolayer-type films of polyoxometallates, certain transition metal oxides (TiO2), and mixed-metal oxides (e.g. ZrO2 and WO3). Among important issues is the existence of large populations of hydroxyl groups, high proton mobility and electronic conductivity, as well as specific interactions with noble metal type catalytic sites (Pt, PtRu, Rh or Ir).
Authors : Jan Augustynski
Affiliations : Centre for New Technologies, University of Warsaw
Resume : There have been numerous attempts over recent years to incorporate plasmonic metal nanostructures into photoelectrochemical (PEC) systems, either semiconductor suspensions or thin film semiconductor photoelectrodes. Although significant enhancements in photon-to-current conversion efficiencies have been claimed for some water splitting photoanodes, they generally did not translate into large net photocurrents. Tungsten trioxide, WO3, is one of few semiconductor materials that combine visible light absorption (Eg = 2.5 eV) with remarkable long-term stability as photoanode during water photoelectrolyses performed in appropriate acidic solutions. Although its band energetics, with the open-circuit photopotential of ca 0.45 V vs RHE, does not allow PEC water splitting in the absence of external bias, WO3 is well suited for the application in a tandem device, combined with a photovoltaic, PV, cell capturing longer solar light wavelengths. The principal limitations to efficient operation of such a device are low visible light absorption coefficients of WO3 related to its indirect optical transition that require use of relatively thick films to form photoanodes. To address this issue we are exploring incorporation into the photoanode of various plasmonic metal nanoparticles. Recent results demonstrate the critical importance of combining the metal NPs with capping agents to limit charge carriers recombination at the semiconductor surface.
Authors : Annette Delices1, Adel Jarboui1, Christian Perruchot1, Mohamed Mehdi Chehimi1, Mohamed Jouini1, Jinbao Zhang2, Lei Yang2, Nick Vlachopoulos2, Anders Hagfeldt2, Vibha Saxena3, Purushottam Jha3, Dinesh K. Aswal3.
Affiliations : 1‐ University Paris‐Diderot Sorbonne‐Paris‐Cité, ITODYS, UMR 7086, 75205 Paris 13, France. 2‐ Dept. Chemistry‐Ångström‐Laboratory, Uppsala University, Lägerhyddsvägen 1, Box‐523n SE‐75120 Uppsala, Sweden. 3‐ Technical Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
Resume : Conducting polymers (CPs) are generally used as hole transporting material (HTM) in dye sensitized solar cells (DSSCs) to replace the unstable HTM couple iodine/iodide (I3-/I-). But till now, CPs direct deposition is done in organic solvent which is difficult because of the high oxidation potential values of the starting organic monomers. This results in DSSCs of very low light conversion efficiency. We present a method that allowed us to perform in aqueous medium on a dye modified TiO2 electrode, in‐situ Photo electro-polymerization (PEP) using 3,4-ethylenedioxithiophene (EDOT) monomer instead of the more expensive dimer Bis‐EDOT previously used. The deposited poly(EDOT) layer is highly uniform and filled perfectly the inside of the porous dye modified TiO2 electrode. This guarantees adequate contact with the dye layer for efficient dye regeneration after electron injection into the TiO2 conduction band. Moreover, the solid state dye sensitized solar cells (ssDSSCs) prepared with Poly(EDOT) obtained from EDOT in aqueous medium show higher light conversion efficiency than those based on PEDOT obtained using EDOT in organic medium. This method is environmentally friendly, easy to implement and the cost of the solid state DSSCs can be reduced drastically when using an organic dye of low‐cost synthesis. J. Zhang et al.; J. Phys. Chem. Let. 2013, 4(23), 4026‐4031; L. Yang et al.; J Phys. Chem. C 2014, 118(30), 16591‐16601.
New Perspective Materials for Catalysis, Electrocatalysis and Energy Production, 2 : Gabriele Mulas, Andrzej Kudelski
Authors : Michael Bernicke, Denis Bernsmeier, Roman Schmack, Bjoern Eckhardt, Erik Ortel and Ralph Kraehnert*
Affiliations : Technische Universit?t Berlin, Berlin, Germany,  BAM - Federal Institute for Materials Research and Testing, Berlin, Germany *firstname.lastname@example.org
Resume : Besides fossil fuels, hydrogen is a promising alternative candidate for chemical energy storage and can be obtained via electrolysis. IrO2 appears to be a stable and active catalyst for OER (oxygen evolution reaction) and the required amount of iridium can be lowered if iridium is used in the form of mixed oxides with Titania. By utilizing Evaporation Induced Self Assembling (EISA) and PEO-b-PB-b-PEO as a pore template, we studied the effect of different chemical precursors in the synthesis of mesoporous Ir/TiOx. All materials were physico-chemical characterized (SEM, TEM, XRD, electrical conductivity BET, OER and active surface area). The contribution will discuss the influence of used precursors, catalyst compositions and calcination temperatures on physico-chemical, electrical and electro-chemical properties. Furthermore, important parameters for the synthesis of highly active OER catalysts will be discussed and the OER performance will be compared with commercial available OER electro-catalysts. References  M. Carmo, D. L. Fritz, J. Mergel, D. Stolten, Int. J. Hydrogen Energy 2013, 38, 4901-4934.  C. J. Brinker, Y. F. Lu, A. Sellinger, H. Y. Fan, Adv. Mater. 1999, 11, 579.  S. Ardizzone, A. Carugati, S. Trasatti, J. Electroanal. Chem. 1981, 126, 287-292.
Authors : Demianenko A.A., Takeda Y., Oyoshi K.
Affiliations : 1 Sumy State University, Sumy, Ukraine; 2 National Institute for Materials Science, Tsukuba, Japan.
Resume : Negative ion beam Au- and high-temperature annealing for structure recrystallization of amorphous AlN-TiB2-TiSi2 coating with characteristic dimension of the short-range ordering regions 0.8-1 nm was used. As a result of high-temperature annealing and subsequent ion implantation is closest to the surface layer forms 3 characteristic zones. First one with doped implanted gold Au-, in 0-40 nm depth, with interplanar spacing 0.244 nm, 0.210 nm corresponding to some increased interplanar spacing lattice of gold planes (111) and (200) respectively. Second one with amorphous-like structural state that evidence by halo figurative type of microdiffraction, in 40-100nm depth. Thirst one with crystalline structural state, in this zone detected inhomogeneous phase , in 100-130 nm depth. Direct measurements by TEM, HRTEM, XRD and SEM with microanalysis showed that annealing at 1300?C in air results to formation of nanoscale 10-15 nm AlN, AlB2, Al2O3 and TiO2 phases, and the ion implantation causes negative ions to a fragmentation (decrease) Au- ions with nanograin sizes 2-5 nm, and to subsequent nanocrystals formation from Au- ?ball? shape with a size of a few nm and to formation of an amorphous oxide film in the depth (surface layer) of the coating due to the ballistic mixing of ions and collision cascades. Amorphous-like structure is promising in the use of such coatings as diffusion barriers in the form of separate elements or as a layer in contacting layered wear-resistant coatings
Authors : 1Seung Beom Kang, 2Min Hwan Kwak, 3Jong-man Joung, 4Nam Ki Son, 5Ki-Chul Kim*
Affiliations : 1POIBOS Inc., Entrepreneurship Development Center O1-406, Mokwon University, 88 Doanbuk-ro, Seo-gu, Daejeon, 302-318, Republic of KOREA; 2Department of Electrical Engineering, Changwon Moonsung University, 91 Chunghon-ro, Changwon, 641-771, Republic of KOREA; 3Distribution Laboratory, KEPCO Research Institute, 105 Munji-ro Yuseong-gu, Daejeon, 305-760, Republic of KOREA; 4DADA Korea Co., Ltd, 86 Habinno, Daegu, 711-822, Republic of KOREA; 5Department of Advanced Chemical Engineering, Mokwon University, 88 Doanbuk-ro, Seo-gu, Daejeon, 302-318, Republic of KOREA.
Resume : In this study, we propose to use terahertz time-domain spectroscopy(THz-TDS) as a novel tool to investigate the complex dielectric and optical characteristics of degraded high voltage insulating oils in the frequency range of 0.1~ 3 THz. For the assessment of degradation, several kinds of used insulating oils in the electrical high power equipment have been characterized by THz-TDS. The degraded high voltage insulating oil showed different dielectric and optical properties compared with non-aged one. The absorption coefficients, the refractive index, the complex dielectric constants and loss tanδ of oils increased as the degradation of insulating oil proceed. The results suggest that THz-TDS is a promising tool for assessing degradation of insulating oils in the electrical high power equipment. Keywords: THz time-domain spectroscopy, insulating oil, electrical high power equipment, degradation assessment
Authors : 1Seung Beom Kang, 2Min Hwan Kwak, 3Nam Ki Son, 4Ki-Chul Kim*
Affiliations : 1POIBOS Inc., Entrepreneurship Development Center O1-406, Mokwon University, 88 Doanbuk-ro, Seo-gu, Daejeon, 302-318, Republic of KOREA; 2Department of Electrical Engineering, Changwon Moonsung University, 91 Chunghon-ro, Changwon, 641-771, Republic of KOREA; 3DADA Korea Co., Ltd, 86 Habinno, Daegu, 711-822, Republic of KOREA; 4Department of Advanced Chemical Engineering, Mokwon University, 88 Doanbuk-ro, Seo-gu, Daejeon, 302-318, Republic of KOREA.
Resume : Terahertz optical and dielectric properties of AlN ceramics fabricated by hot pressed sintering are investigated by THz time-domain spectroscopy in the frequency range of 0.2 to 3.5 THz. The measured properties of the pure AlN ceramics are compared with those of Y2O3-added AlN ceramics. Two prominent resonance modes, which are essentially responsible for the dielectric properties of the Y2O3-added AlN in terahertz regime, are characterized at ωTO1/(2π)=2.76 THz (92 cm-1) and ωTO2/(2π)=18.2 THz (605 cm-1) and are well described by the pseudo-harmonic oscillator model through theoretical fitting. The resonance ωTO1 at 2.76 THz is proposed to be due to the formation of a YAG (Y3Al5O12 ) secondary phase in Y2O3-added AlN ceramic. From the experimental results, good correlation is observed between the prominent peak of YAG secondary phase at 2.76 THz and thermal conductivity. Additionally, there is a high correlation between densification and refractive index of AlN ceramics fabricated by hot pressed sintering. Keywords: THz time-domain spectroscopy, AlN, thermal conductivity, densification
Authors : Yueli Liu, Linlin Wang, Chao Zhang, Wei Jin, Peng Zhou, Keqiang Chen, Wen Chen
Affiliations : State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, and School of Material Science and Engineering, Wuhan University of Technology, Wuhan 430070, P. R. China
Resume : Titanium oxide is widely used to remove both organic and inorganic pollutants from various environmental media. However, the practical application of TiO2 as a photocatalyst is limited by its wide band gap of 3.2 eV, which only absorbs the UV light below 385 nm, leading to the practical difficulty in application. The photocatalytic property of the TiO2 can be improved by the modified with V2O5 semiconductor material, and the absorption edge is extended due to the narrow band gap, which makes V2O5/TiO2 system as an effective catalytic material in photocatalytic application. In the work，TiO2 hollow spheres with nanometer size were prepared by a template method, polystyrene (PS) and tetrabutyl titanate (TBOT) were employed as template and titanium source, respectively. Then TiO2@V2O5 core-shell microspheres were prepared through a sol-gel method with calcination, and it was proved that TiO2@V2O5 core-shell microspheres were successfully synthesized by XRD patterns, SEM images as well as TEM images. The as-prepared TiO2@V2O5 core-shell microspheres were used as the photocatalyst in the degradation of gaseous benzene in UV and visible light region. It was found that the photodegradation rate of TiO2@V2O5 core-shell microspheres was greatly enhanced, especially in the visible light region. As the V2O5 shell may decrease the band gap of the microspheres, which enables to enlarge the light absorption range to produce more photo-generated electrons. Moreover, the pn heterojunctions
Authors : Konrad Trzciński1, Mariusz Szkoda1, Katarzyna Siuzdak2, Mirosław Sawczak2, Anna Lisowska-Oleksiak1
Affiliations : 1Department of Chemistry and Technology of Functional Materials, Chemical Faculty, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland; 2Centre for Plasma and Laser Engineering, The Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Science, Fiszera 14, 80-231 Gdansk, Poland.
Resume : The bismuth vanadate is an n-type semiconducting material that attracts great attention due to its photoactivity, especially high efficiency of water photooxidation. The relatively narrow energy band gap (Eg = 2.45 eV) makes BiVO4 competitive to other wide band gap photocatalysts e.g. TiO2 and ZnO. However, the major drawback of BiVO4 is the poor efficiency of charge carrier separation. The different strategies were applied to improve BiVO4 photoactive properties e.g. formation of p-n junction. In this work we are focused on composite formation BiVO4 - PEDOT/PSS having a character of a p-n junction. The BiVO4 layers were deposited onto the FTO using pulsed laser deposition technique and composite was fabricated via a potentiostatic electropolymerization of PEDOT/PSS on the BiVO4/FTO substrate. The presence of polymer was confirmed using Raman spectroscopy. According the UV-Vis absorbance measurements, the composite material exhibits enhanced absorbance capability in visible range in comparison to its pure counterparts. The surface morphology of films before and after polymer deposition were inspected using SEM. The photocatalytic properties of the composite materials as well as bismuth vanadate layers were examined towards the degradation of methylene blue and as well as photoanodes for water splitting process carried out under VIS illumination. Financial support from the National Science Center (2012/07/D/ST5/02269) is gratefully acknowledged.
Authors : Mariusz Szkoda1, Katarzyna Siuzdak2, Mirosław Sawczak2, Jacek Ryl3, Jakub Karczewski4 Anna Lisowska-Oleksiak1
Affiliations : 1Department of Chemistry and Technology of Functional Materials Chemical Faculty, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland; 2Centre for Plasma and Laser Engineering The Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Science Fiszera 14, 80-231 Gdansk, Poland; 3Department of Electrochemistry, Corrosion and Materials Engineering, Gdańsk University of Technology, Narutowicza 11/12, 80-952 Gdańsk, Poland; 4Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland
Resume : Highly ordered TiO2 nanotubes (TNT) are the one of most investigated photosensitive materials due to their unique properties such as, photo and chemical stability, low cost, non-toxicity and high specific surface area. As a result, TNT have been used in various field, such as gas sensing, solar cells, water splitting and air purification. However, due to their large band gap of 3.2 eV, different strategies were applied to modify titania structure or surface in order to shift TNT photoactivity towards visible range. Several studies have shown that doping TiO2 with nonmetals, such as nitrogen, carbon or boron could increase significantly visible-light activity. Here, the boron doping was performed as an additional electrochemical treatment of as-sensitized TNA in 0.5 M solution of H3BO3. The obtained materials were characterized by SEM, using spectroscopic techniques (UV-Vis, Raman, XPS, photoluminescence spectroscopy) and electrochemical methods. The B-doping shifts the absorption edge of TNT to the visible light region. Under the light irradiation, the B-doped TNT layer show higher photocatalytic activity towards degradation of methylene blue than pure titania. Moreover, the simple doping of TNT leads to enormous enhancement of generated photocurrent recorded at E = 0.5 V vs. Ag/AgCl/0.1KCl from 44 µA/cm2 to 310 µA/cm2 for undoped and doped electrode, respectively. Financial support from the National Science Center (2012/07/D/ST5/02269) is gratefully acknowledged.
Authors : A. I. Popov (1), I. Kudryavtseva (2), A. Lushchik (2), E. Feldbach (2), J. Zimmermann (3), E. Aleksanyan (4), A. Moskina (1), J. Purans (1)
Affiliations : (1) Institute of Solid State Physics, University of Latvia, 8 Kengaraga, LV-1063 Riga, Latvia (2) Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu, Estonia (3) Fraunhofer-Institut für Silicatforschung, Brentanostr. 2, 63755 Alzenau, Germany (4) A.I. Alikhanyan National Science Laboratory, 2 Br. Alikhanyan Str., 0036 Yerevan, Armenia
Resume : ScF3 has a simple cubic ReO3 type structure down to at least 10 K and exhibits a rare property of isotropic negative thermal expansion (NTE) over a large temperature range. In order to reveal the manifestations of the NTE effect in optical spectra, we have performed the following investigations: (a) cathodoluminescence analysis of ScF3 single crystals, (b) VUV-luminescence excitation using synchrotron radiation at MAX-Laboratory in Lund, (b) Thermally stimulated luminescence (TSL) study between 80 and 350 K, excited by an electron-beam (10 keV) or VUV radiation. From the TSL data analysis and the comparison with other metal fluorites, we can conclude that in ScF3 there is the effective self-trapping of holes in the form of Vk cen-tres and their thermal destruction occurs at about 100 K. From the creation (excitation) spectra of several TSL peaks as well as the VUV-luminescence excitation spectra, we can conclude that the value of band gap energy in ScF3 exceeds 11 eV.
Authors : A.Mikolajczuk-Zychora1, A.Borodzinski1, P.Kedzierzawski1, B.Mierzwa1, M.Mazurkiewicz2, E.Ciecierska2, A.Zimoch1, M.Opallo1
Affiliations : 1) Institute of Physical Chemistry PAS, Warsaw, Poland 2) Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw, Poland
Resume : We present the synthesis of highly active palladium catalysts for electro-reduction of oxygen in direct formic acid fuel cells. The catalysts were prepared by reduction of palladium(II) acetate dissolved in ethanol. Hydrazine was used as reducing agent. The palladium ions were reduced on the carbon black (Vulcan) or multiwall carbon nanotubes (MWCNTs) surface. The supports were either treated in nitric acid for 4 hours at 80ºC, or used as received. The structure of prepared catalysts has been characterized by TGA, XRD and HR-TEM. The catalysts were used at the cathode in direct formic acid fuel cell (DFAFC). The catalysts, which were prepared on functionalized supports show higher activity in the cathode in DFAFC than catalysts prepared on raw supports. Our results indicated that treatment of carbon support in nitric acid(V) has influenced the activity of the catalysts. The palladium catalyst supported on Vulcan, which is refluxed in nitric acid(V) for 4 hours at 80ºC, shows the best specific power in direct formic acid fuel cell. The specific power for the best Pd/Vulcan catalyst is comparable to the commercial 20% wt. Pt/Vulcan (Premetek). The increased activity of catalysts, which supports were functionalized, may be due to removal the surface impurities from supports during their treatment in nitric acid for 4 hours at 80ºC or due to the presence of crystallographic index planes of palladium, which are preferred for electro-reduction reaction of oxygen.
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Authors : Jolanta Światowska
Affiliations : PSL Research University, Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris, 11 rue Pierre et Marie Curie, 75005 Paris, France
Resume : Understanding the electrode processes occurring at the electrode/electrolyte interface and in the bulk electrode material is necessary for developing the electrochemical performances of lithium-ion (LIB), sodium-ion, sulfur or metal-air batteries. The main electrode processes are insertion/extraction reactions that induce changes in the host electrode materials; they are accompanied by decomposition of electrolyte that leads to formation of a solid electrolyte interphase (SEI) layer on the electrode surface. Two principal surface-sensitive techniques, particularly suitable for analyzing these processes are: X?ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Our approach is to use model, nanometer-thick electrodes with a good surface finishing with a minimum roughness. New types of high capacity negative-electrode materials having a potential application in LIB will be presented: a conversion-type electrode consisting of iron oxide and an alloying-type electrode consisting of silicon. Apart the chemical composition of the SEI layer formed on the surfaces of these electrodes, the evidence of a dynamic increase/decrease of SEI upon lithiation/delithiation, and surface modifications upon cycling will be discussed. The irreversible chemical bulk modifications and volume changes of the electrode materials will be also evidenced by ToF-SIMS ion depth profiles. These modifications are detrimental to performance of battery cycle life.
Authors : Pavel V. Krasovskii (1), Olga S. Malinovskaya (2), Andrey V. Samokhin (1), Yury V. Blagoveshchenskiy (1), Valery А. Kazakov (2), Artem А. Ashmarin (2).
Affiliations : (1) A.A. Baikov Institute of Metallurgy and Materials Science, Russian Academy of Sciences, Leninskii pr. 49, Moscow 119991, Russia; (2) SSC Keldysh Research Centre, Onezhskaya 8, Moscow 125438, Russia.
Resume : The analytical studies are presented on the chemical composition and bonding in the near-surface region of the nanophase tungsten carbides, particularly in connection with their promising uses in catalysis and hardmetal industry. The materials are produced through a DC thermal plasma technology that has reached a significant level of development and upscaling. The analytical information has been primarily gathered using X-ray photoelectron spectroscopy (XPS). The XPS analysis was combined with Raman spectroscopic, HRTEM, and thermal evolution studies. The analytical work resulted in a distinction between the major surface conditions for the nano-WC, including that equilibrated with the bulk. The analytical determinations concerned the nature/thickness of the surface segregations of carbon, the coverage/bonding of adsorbed oxygen, the effect of the average bulk stoichiometry on the surface composition, etc.
Solid State Materials Characterization and Electron Spectroscopy, 2 : Aleksander Krupski
Authors : Pavel Jelinek
Affiliations : Nanosurf Lab, Institute of Physics of the AS CR, Prague, Czech Republic
Resume : The recent progress in Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM) using functionalized tips provided unprecedented atomic resolution of single organic molecules [1,2]. Here we will provide insight into the origin of the high-resolution AFM/STM images . We will show that the mechanism could also stand for atomic resolution observed in electrochemical STM  or high-resolution STM images taken in contact mode . We will also briefly discuss what other information can be gained from the high-resolution AFM/STM images going beyond the simple imaging of chemical structure.  L. Gross et al., Science 325,1110 (2009).  C. Weiss et al., Phys.Rev.Lett. 105, 086103 (2010).  P. Hapala et al., Phys. Rev. B 90, 085421 (2014); P. Hapala et al., Phys. Rev. Lett. 113, 226101 (2014).  P. Broekmann, M. Wilims, K. Wandelt, Surf. Rev. Lett. 06, 907 (1999)  J.A. Stroscio, R.J. Celotta, Science 306, 242 (2004).
Authors : Elena Florentina Grosu1 Ken Eichi Katsumata, Kei Ikeda2, Gabriela Carja1
Affiliations : 1 Department of Chemical Engineering, Faculty of Chemical Engineering and Environemntal Protection, Tecnhical University Gh. Asachi of lasi, Bd. Mangeron no.71, Iasi 700554, Romania 2 Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori, Yokohama, 226-8503, Japan
Resume : Self-assemblies of nanoparticles of gold and the anionic clay matrices of layered double hydroxides (LDHs) were fabricated using the manifestation of the structural memory effect of the LDHs in AuCl3 aqueous solutions, at room temperature . We used specific compositions of ZnCeAlLDHs containing Zn2+, Ce3+ and Al3+ + as cations in the LDHs layers. Controlled thermal treatment of Au/LDHs assemblies gave rise to the complex systems of nanosized mixed oxides. Powder X-ray diffraction (PXRD), high resolution transmission electron microscopy (TEM, see Figure 1), Fourier transform infrared spectroscopy (FTIR) and UV-Visible spectroscopy (UV-Vis) were used to investigate the structural, composition and size-morphology characteristics of the Au/ZnCeLDHs. Results point out that Au/LDHs nanoarchitectonics consists of small nanoparticles of Au that are highly dispersed on much larger nanoparticles of the LDHs while the composition of the evolved mixtures of mixed oxides is a function of the composition of the LDHs precursor. UV-Vis analysis indicates specific plasmonic responses of Au nanoparticles under Vis and UV light revealing the photo-cooperativity of the components in the nanostructured gold-clay system. X-ray photoelectron spectroscopy (XPS) was used to investigate the state of gold on the surface of the specific LDH matrices. Acknowledgment: The authors are grateful for the financial supports from the Romanian National Authority for Scientific Research, CNCS-UEFISCDI (PN-II-ID-PCE-75/2013), the Kazuchika Okura Memorial Foundation, Planting Seeds for Research program from Tokyo Institute of Technology, Grant-in-Aid for Young Scientists (A; 25708037) from Japan Society for the Promotion of Science (JSPS), and by the project Development Base of Advanced Materials Development and Integration of Novel Structured Metallic and Inorganic of the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan. 1. S. Kawamura , M. C Puscasu, Y. Yoshida, Y. Izumi, G. Carja, App. Cat. A, in press DOI: 10.1016/j.apcata.2014.12.042.
New Perspective Materials for Catalysis, Electrocatalysis and Energy Production,3 : Piotr Żabiński, Grzegorz Sulka
Authors : Gabriele Mulas 1, Sebastiano Garroni 1, Elisabetta Masolo 1, Stefano Enzo 1, Francesco Spanu 1, Elisa Tolu 1, Maria Dolores Barò 2, Eva Maria Pellicer 2, Jordi Sort 2
Affiliations : 1 Department of Chemistry and Pharmacy, University of Sassari and INSTM, Via Vienna 2, I-07100 Sassari, Italy 2 Departament de Física, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
Resume : The expected widespread diffusion of several energy related technologies relies upon the development of innovative materials, which could allow overcoming some current limitations. New chemical compositions as well as structural and thermodynamic conditions are then explored in order to develop and improve the properties different devices for energy storage and conversion including secondary batteries, supercapacitors, hydrogen production and storage systems, fuel cells, piezoelectric devices. To this regard is recent the attention to nanosized materials confined within mesoporous matrices which combine thermodynamic metastability with several advantageous morphological features as high surface area, pore diameter between 2-50 nm, good corrosion resistance etc. We focus here on the synthesis and the applicative properties of new materials related to the above cited technologies. A series of mesoporous materials were synthesized by sol-gel methods, using EISA (Evaporation Induced Self-Assembly) and Hard Templating approaches. Composite systems were also prepared by melting infiltration or wet impregnation of nanosized phases within the porous matrixes. A detailed characterization of the prepared material and the investigation of their reactivity and applicative properties is fulfilled through a number of instrumental techniques.
Authors : Sylvain Regny, Meriem Lamouchi, Cédric Desroches, Arnaud Brioude, Mathieu Maillard
Affiliations : Laboratoire des Multimatériaux et Interfaces, UMR 5615, CNRS-Université Lyon 1 43 bd du 11 Novembre 1918, F-69622 Villeurbanne, France
Resume : This work relates to a large scale synthesis of gold-titania core shell nanoparticles and their application to photo-activated reactions. Nanoparticles have been synthesized using an innovative process involving titanyl solutions, allowing large scale synthesis of crystalline gold-titanium dioxide nanoparticles, up to 0.7 g.L-1. The absence of alkoxyde allowed us to work in aqueous media, with low cost chemicals and a controlled reactivity, which is a key parameter for industrial up-scaling. These nanoparticles have been successfully assembled into compact electrodes and probed using electrochemical methods to describe electrochemical exchange between metallic core, semi-conductor shell and various electrolytes. Reaction between gold nanoparticles and triiodide has been scrutinized to explain limitation of plasmon enhancement in standard DSSC involving iodine based electrolytes.
Authors : Jan Krajczewski, Sebastian Wojtysiak, Andrzej Kudelski
Affiliations : University of Warsaw, Faculty of Chemistry, ul. Pasteura 1, 02-093 Warsaw, Poland
Resume : Addition of some other metals to platinum causes significant increase of its catalytic activity towards ethanol electrochemical oxidation. In this work various M@Pt core-shell nanoparticles and hollow Pt nanoparticles were synthesized and their catalytic activity towards ethanol electro-oxidation was determined and compared with the catalytic activity of one element Pt nanoparticles. We found that higher catalytic activity towards ethanol oxidation of some core-shell nanoparticles than solid Pt nanoparticles is rather not caused by different adsorption of CO molecules on solid Pt and core-shell nanostructures. We suppose that better performance of core-shell M@Pt nanoparticles than one elements Pt nanoparticles towards ethanol electrochemical oxidation can be explained as follows: core-shell nanoparticles are probably much more defected than one-element nanoparticles, hence the M@Pt nanoparticles posses greater number of active sites (kinks, adatoms, and so on) for ethanol electrochemical oxidation.
Authors : Jan Krajczewski, Karol Kołątaj, Andrzej Kudelski
Affiliations : University of Warsaw, Faculty of Chemistry, ul. Pasteura 1, 02-093 Warsaw, Poland
Resume : Silver nanoparticles have a number of interesting optical, catalytic and antibacterial properties. Many silver nanostructures may be synthesized using various photochemical reactions. In this work we describe the influence of stabilizing agent on the photochemical transformation of small, spherical silver seeds into bigger anisotropic nanostructures. In the first stage of the photochemical transformation, silver clusters (silver seeds nanoparticles) are partially dissolved. Then, Ag+ cations from the solution are photocatalyticaly reduced to Ag0. The photocatalytic reduction of Ag+, and hence deposition of metallic silver, occurs preferentially at such places of the silver nanoclusters, at which strong surface plasmons are excited (usually sharp etches or slits between nanoparticles). In this work we used sodium salts of many various poli-carboxylic acids as stabilizing agents. We found that used stabilizing agent significantly influences the photo-transformation process (finally obtained nanostructures have different shape and size). Many synthesised silver nanostructures have very interesting plasmonic properties. For example, we found that light-induced transformation of silver sols may be used to significantly increase their activity in surface-enhanced Raman scattering (SERS) measurements.
Authors : B.O. Postolnyi (1, 2), O.V. Bondar (1), O.V. Sobol (3), J.P. Araujo (2), A.D. Pogrebnjak (1)
Affiliations : (1) Sumy State University, 2, Rymskogo-Korsakova st., 40007 Sumy, Ukraine; (2) IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Department of Physics and Astronomy, Faculty of Science, University of Porto, 687, Campo Alegre st., 4169-007 Porto, Portugal; (3) National Technical University «Kharkiv Polytechnic Institute», 21, Frunze st., 61002 Kharkiv, Ukraine
Resume : Fabrication of protective coatings with various functional purposes is one of the main task of industry, material science and solid state physics. This work is focused on study and characterization nanocomposite protective coatings based on metal nitrides MoN. Samples were obtained on high-speed steel X18H9T substrate using Arc-PVD deposition in vacuum-arc unit Bulat-6. Negative substrate voltage Us=-(100÷200) V and pressure of nitrogen atmosphere in chamber p=(0,2÷0,5) Pa were used. The thickness of coating was ranged from 7 µm up to 22 µm. Element composition analysis of coatings were performed using energy-dispersive spectroscopy (EDS), morphology of coatings and surface topography were studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM) respectively. Structure-phase composition of coatings was investigated by X-ray diffraction analysis (XRD). The hardness and elasticity values of coatings are also shown. Relations between deposition conditions and features of the structure, composition and physical-mechanical properties of obtained coatings. The interaction at the interface between the steel substrate and MoN coatings under stress was found.
Authors : 1Yeoung-Ah Noh, 2Jin-Ho Jang, 1Ki-Chul Kim*
Affiliations : 1Department of Advanced Chemical Engineering, Mokwon University, 88 Doanbuk-ro, Seo-gu, Daejeon, 302-318, Republic of KOREA; bPL Co., Ltd, S9-505, 125 Dongseo-daero, Yuseong-gu, Daejeon, 305-719, Republic of KOREA.
Resume : The anti-reflective coating using SiO2 nanoparticles (NPs) is used to improve the energy conversion efficiency of the Si solar cells . In addition, TiO2 NPs are known as well decomposing the organic contaminants by photo-catalytic effect . In this study, we synthesized SiO2 and TiO2 NPs with various size and surface morphology. The spherical SiO2 NPs with smooth surface are synthesized using tetraethyl orthosilicate (TEOS), ethanol, ammonia hydroxide, and water. The particle size of the silica NPs is controlled by ammonia hydroxide and stirring intensity. The wrinkled silica NPs are synthesized using TEOS, cetylpyridinium bromide, urea, iso-propanol and water. The density of wrinkles is controlled by isopropanol and n-butanol. The TiO2 NPs are synthesized using titanium (IV) butoxide, acetyl acetone, 1-butano, nitric acid and water. The anti-reflective and self-cleaning SiO2/TiO2 nano-composite films are prepared by dip or spin coating using the synthesized SiO2 and TiO2 NPs. The optical properties and surface morphology of the nano-composite films are characterized by UV-visible spectrometer, SEM, AFM, and TEM, respectively. Keywords: anti-reflective, self-cleaning, nano-composite film, surface structures  G. San Vicente et al., Thin Solid Films, Vol. 517, p. 3157 (2009).  A. L. Linsebigler et al., Chem. Rev., Vol. 95, p. 735 (1995).
Authors : N. Korsunska1, M. Baran1, Yu. Polishchuk1, V. Kladko1, Ye. Venger, L. Khomenkova1, M. Kharchenko2, O. Gorban2, T. Konstantinova2
Affiliations : 1)V. Lashkaryov Institute of Semiconductor Physics, 45 Pr. Nauky 03028 Kyiv Ukraine; 2) O.O.Galkin Institute for Physics and Engineering, 46 Pr. Nauky 03028 Kyiv Ukraine
Resume : In recent years Cu-doped Y-stabilized ZrO2 composites are intensively investigated due to their excellent properties (such as environmental degradation, catalytic activity, tribologocal behaviour). These latter were found to be depended on Cu localisation. Therefore, the effect of calcination temperature (Tc=500-1100C) on Cu localisation in such composite was investigated byXRD, EPR and photoluminescnece (PL) methods. The samples calcinated at Tc=500-800C show the tetragonal ZrO2 phase mainly. EPR spectra demonstrate the signal caused by Cu-related surface complexes in this Tc range. At the same time, the Tc increase from 500 to 800C results in the lattice constant decrease along with the decrease of EPR signal intensity. This testifies to Cu incorporation into nanocrystals from the surface entities that is accompanied by the PL quenching due to increase of intrinsic defect density. Besides, the additional green PL band, which can be ascribed to Cu atoms at Zr sites, appears. The futher Tc increase (up to 1000C) causes the transformation of tetragonal phase to monoclinic one, the higher Cu content, the higher the temperature of this transformation. Simultaneously, the tetragonal lattice constant and total PL intensity increase. This can be explained by the outward Cu diffusion from nanocrystals that is confirmed by the decrease of green PL band intensity and the appearance of surface EPR signal for samples calcinated at Tc=1100C.
Authors : A.I. Gudymenko, V. P. Kladko, A. S. Nikolenko, R. K. Savkina, A. B. Smirnov, V. V. Strelchuk
Affiliations : V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, Kiev, Ukraine
Resume : Extreme conditions of the ultrasonic cavitation such as local temperature and the pressure are widely used in chemistry, as for example to synthesize nano-materials, to enhance the electrochemical reactions and to modify the surface properties of electrodes, as well as to generate the novel materials in a liquid medium. The ultrasonic irradiation is a powerful tool in promoting of the chemical reactivity in the liquids at solid surfaces also. In our experiments described here, an attempt to drive the chemical and structural transformations on a semiconductor surface by the ultrasonic cavitation effect was made. The properties of the silicon samples subjected to cavitation impacts have been studied. Optical, atomic force and scanning electron microscopy techniques, Raman spectroscopy as well as energy dispersive X-ray spectroscopy and X-ray diffraction measurements were used. It was found the dendrite-like micron-scale array formation as well as a change of the chemical composition up to the new phase occurrence inside the ultrasonically structured region. In particular, the sonochemical synthesis of CaSiO3 compound on the silicon surface was fixed. Calcium inosilicate have been studied as materials for hard tissue repair, artificial bones and dental roots. Biomaterials containing CaOSiO2 appeared to excellent bioactivity and were found to bond have to living bone and soft tissue.
Authors : Octavian Ciobanu, Gabriela Ciobanu
Affiliations : Grigore T. Popa University of Medicine and Pharmacy, Faculty of Medical Bioengineering, Universitatii Str., no. 16, Iasi, 700115, Romania; Gheorghe Asachi Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, Prof. dr. docent Dimitrie Mangeron Rd., no. 63, Iasi, 700050, Romania
Resume : In recent years, a greater demand for dental and orthopedic implants can be noticed. The clinical success of these implants is related to their early osseointegration and this is related to their surface properties. Surface modification of titanium implants for bone contacting applications is a very active field of research. Presently, the approaches to the surface modification of titanium implant devices involve surface topography modification or the application of inorganic/organic coatings. In this research, the hydroxyapatite-collagen-silver coatings have been deposited onto titanium implants by a combined method involving hydroxyapatite/collagen electrochemical deposition, combined with silver ions reduction and in-situ crystallization processes on titanium surface. The electrolytic processes implies the nucleation and growth of hydroxyapatite crystals on the surface of the titanium implant in a simulated body fluid under physiological conditions of pH and temperature, applying a constant current for different periods of time. The collagen has been used to modify titanium surfaces in order to enhance their bioactivity. The silver incorporation into hydroxyapatite coatings is an alternative that can provide good antibacterial properties of these coatings. The morphology, composition and phase structure of the hydroxyapatite-collagen-silver coatings were characterized by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX) and X-ray diffraction (XRD). The implants were tested against Staphylococcus aureus and Escherichia coli and the obtained data were indicative of good antibacterial properties of the materials.
Authors : Katarzyna Grochowska1, Katarzyna Siuzdak1, Michał Sokołowski2, Jakub Karczewski2, Mariusz Szkoda3, Gerard Śliwiński1
Affiliations : 1Centre for Plasma and Laser Engineering, The Szewalski Institute, Polish Academy of Sciences, 14 Fiszera St., 80-231 Gdańsk, Poland; 2Faculty of Applied Physics and Mathematics, Gdańsk University of Technology, Narutowicza 11/12 St., 80-233 Gdańsk, Poland; 3Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12 St., 80-233 Gdańsk, Poland
Resume : Currently, roughened metal nanostructures are widely studied as highly sensitive enhanced Raman scattering (SERS) substrates that show application potential in biochemistry, food safety or medical diagnostic. In this work, we report on optical and structural properties of thin gold films deposited on highly ordered nano-patterned titanium templates for SERS applications. The templates are formed in following processes: a) formation of TiO2 nanotubes via a two-step anodization, b) etching of TiO2 nanotubes via overnight immersion in oxalic acid after the first and second anodization step. SEM images reveal the formation of honeycomb nanostructures with the cavity diameter of 80 nm. The thin (5-20 nm) quasi-continuous Au films are produced by pulsed laser deposition (PLD) using the UV (355 nm) laser operated at fluence up to 1.5 mJ/cm2 in vacuum conditions at room temperature. Due to strongly inhomogeneous distribution of the electromagnetic field in the vicinity of the Au film irregularities/discontinuities the measured average SERS signal is markedly higher than observed for bare Ti templates. It is shown that the enhancement factor can be optimized by adjusting the thickness of the deposited Au layer. Results confirm that the bimetal structures consisting of PL-deposited Au films on Ti templates can be used in surface enhanced sensing. KG and KS acknowledge the National Science Centre of Poland for financial support via grants 2012/07/N/ST5/02139 and 2012/07/D/ST5/02269.
Authors : O. Naumenko, A. Oleshkevych, S. Voloshko, S.I. Sidorenko
Affiliations : National Technical University of Ukraine, Kyiv Polytechnic Institute, Peremogy Ave. 37, 03056 Kyiv, Ukraine
Resume : Nanoscale factor significantly affects diffusion controlled processes such as structural and phase transformations. Nowadays those factors have not been thoroughly studied, and available results are quite unusual and controversial. Interdiffusion in nanofilm systems in comparison with bulk materials is characterized by more extensive mass transfer at low temperatures. This phenomenon is caused not only by high defects concentration and small diffusion distances, but also by significant surface influence. In thin films sequence of phase formation may vary from phase formation for bulk materials, and nanoscale factor plays an important role in causing these differences. Grazing-incidence x-ray technique and secondary neutral mass spectrometry have been applied to study layer-by-layer concentration, phase composition and phase transformation in Pd(30nm)/Ho(20nm)/SiO2 thin films. According to the phase equilibrium diagram for bulk materials next phases must be formed: Ho5Pd2, Ho3Pd2, HoPd, Ho3Pd4, Ho2Pd3, HoPd2, HoPd3. However, results show that after annealing in vacuum and in hydrogen formation of HoPd3 intermetallic phase only was registered. Also reflexes from Ho2O3 and HoH2 were registered on the surface using GIXRD. An interplay of phase formation at the outer surface and in the bulk has been investigated and it was discovered that the domination of processes on the external surface inhibits phase formation in the bulk and the other way around.
Authors : Alexander Sherstnyov, Eugene Chubenko, Sergey Redko, Vladimir Petrovich, Vitaly Bondarenko
Affiliations : Belarusian State University of Informatics and Radioelectronics, P. Brovka str. 6, Minsk 220013, Belarus
Resume : In this paper we study the formation of functional nanocomposite materials by electrochemical deposition of zinc oxide (ZnO) nanostructures inside the porous silicon (PS) template. These nanocomposites are promising for sensor, photovoltaic and photoelectrochemical applications. PS template formation was carried out in 9 % HF solution in pulsed galvanostatic mode in darkness at 120 mA/cm2. ZnO electrochemical deposition was carried out in dimethylsulfoxide based solutions containing 0.03 M ZnCl2 and 0.1 M KCl and also polyoxyethilene (POE) and H2O2 as additives. According to SEM analysis after 60 min of ZnO deposition at different current densities nucleation of separate ZnO nanoparticles occurs all over the surface of PS layer even at the bottom parts of pores. Presence of POE in the solution helps to avoid closing of the pore openings at the high ZnO deposition current densities (>0.5 mA/cm2). Addition of 5 mM H2O2 in the solution improves stoichiometry of deposited ZnO. Catalytic activity and gas sensing ability of PS surface functionalized by electrodeposited ZnO were investigated. This research is supported by the Grant of Ministry of Education of Republic of Belarus for students, and Belarus Government Research Programs Nanotechnology and nanomaterials, grant 2.4.16; Electronics 2015, grant 1.1.14.
Authors : Cezariusz Jastrzebski1, Dariusz Szmigiel2, Rafal Dobrowolski2, Krzysztof Świtkowski1, Monika Seniut1, Rafal Maselek1, Wojciech W. Brylinski1
Affiliations : 1 Faculty of Physics, Warsaw University of Technology; 2 The Institute of Electron Technology (ITE)
Resume : Silicon based electronics is often limited by phenomena occurring at the new structure-silicon interface. Most of the thin films used in micro-technology exhibit stress, which might affect both further processing during a fabrication cycle and final performance of fabricated micro-devices. Stress reducing is the key for improving of such opto- and/or electronic devices. Amorphization of silicon surface is one way of obtaining the goal. The silicon thin films were deposited using ASM LPCVD furnace on 100 mm oxidised silicon wafers at wide range of process conditions. The films of different structural (amorphous and polycrystalline) and mechanical (different stress level) properties were obtained. Raman studies for various wavelength excitation were performed. Confinement of phonons in a finite dimension of nano grains results in a change in the line-shape and position of the peaks in first order Raman spectrum. The average size of silicon nano grains in the thin silicon films have been obtained on the base of the spectroscopic studies. The maps of the grain size distribution to analyze the nonuniformity of the silicon film surface will be presented. Additionally appearance of specific surface and interface vibrational contribution for surface state evaluation will be discussed.
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Authors : Wojciech Swieszkowski
Affiliations : Faculty of Materials Science and Engineering, Warsaw University of Technology
Resume : The aim of the presentation is to show evidences how important are scaffolds and their surface properties in regenerative medicine. There are several tissues that show limited self-healing abilities. It was proven that the critical defects of peripheral nerves and bones usually do not heal themselves. One of the most promising methods in treatment of such defects is tissue engineering and using of bioactive scaffolds that could mimic the extracellular matrix (ECM) and assist in tissue regeneration. For instance, bio-composite nanofibrous scaffolds made from synthetic and natural polymeric blends provide suitable substrate for tissue engineering and it can be used as nerve guides eliminating the need of autologous nerve grafts. Nanotopography or orientation of the fibers within the scaffolds greatly influences the nerve cell morphology and outgrowth, and the alignment of the fibers ensures better contact guidance of the cells. In bone tissue engineering the composition of the scaffolds, their mechanical properties, degradation kinetics, and surface properties (wettability, surface energy, and roughness) strongly influence response of human bone marrow mesenchymal stromal cells (HBMC) and whole regeneration process. By optimising these parameters using smart materials and advance biofabrication methods we will be able to control cells reaction and enhance process of new tissue formation.
Authors : Ludek Hromadko*1, Eva Koudelkova2, Miroslav Tejkl3, Jaroslava Moravkova3, Jan Buk3, Roman Bulanek2, Jan M. Macak1
Affiliations : 1Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Nam Cs. Legii 565, Pardubice 530 02, Czech Republic *email: email@example.com; 2Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, Pardubice 530 02, Czech Republic; 3Pardam Ltd., Jindrisska 2025, Pardubice 530 02, Czech Republic
Resume : An efficient separation of the air-borne moisture using silica sorbents is one of key operations in a range of industries, including electrotechnics, machinery, food preservation, chemistry to either preserve the product quality and to prevent degradation (due to aging, corrosion, decaying), or to remove quantitatively moisture from the air, whenever a low moisture air must be used (wood, paper industries). The specific surface of a sorbent material is very important parameter for high sorption capacity and should be as high as possible. This is possible using nanostructured sorbent, typically in the form of particles. However, they cannot be used repetitively as their desorption is tedious and costly. Large-scale production technologies for these materials are also often not available. Nanofiberous silicagels offer great moisture-capture capabilities and kinetics that can overcome conventional silicagels at comparable price. Moreover, they are capable of recovery at lower temperatures. Larger number of desorption cycles prolonging lifetime of these sorbent is realistic, thus making an additional positive cost figure. The presentation will show recent results in the synthesis of new efficient sorbent based on silica nanofibers using advanced production technology force spinning that has recently attracted large scientific as well as industrial attention. In particular, we will present results on surface and sorption characteristics of this material.
Authors : Torben R. Jensen
Affiliations : iNANO and Department of Chemistry, Aarhus University, Denmark.
Resume : We have plenty of renewable energy available but sun and wind are unevenly distributed over time and geographically, therefore energy storage is increasingly important. Metal hydrides have extremely diverse chemistry, structures and reactivity and often high energy density . We have recently developed new synthesis strategies combining mechano-chemical and solvent based methods, which are also useful for coordination chemistry. A series of 30 new complex borohydride perovskite-type materials are presented with interesting photophysical, electronic and hydrogen storage properties. Furthermore, anion-mixing provides a link to the known ABX3 halides . New metal hydrides, which are fast lithium, sodium and magnesium ion-conductors are also discovered and are now tested in batteries . A fascinating structural chemistry is discovered within metal borohydrides, e.g. up to 30% empty space in the porous structures and physisorption of small molecules. Recently, we stabilized NH4BH4 with extreme hydrogen density, 24.5 wt% H2 . Tailoring materials properties by nanoconfinement is also promising . We conclude that the chemistry of hydrides is very divers, towards rational design of multi-functional materials, including ion-conductors for batteries, hydrogen storage etc. Ref:  Ley, et al, Mater. Today, 2014, 17(3), 122.  Schouwink, et al, Nature Comm., 2014, 5, 5706.  Ley, et al, Chem. Mater. 2012, 24, 1654.  Nielsen, et al, Nanoscale, 2011, 3, 2086.
Functional Materials/Nanomaterials: 1 : Stanisław M. Filipek
Authors : A.Calka
Affiliations : University of Wollongong, Faculty of Engineering and Information Sciences, Wollongong, NSW2522, Australia
Resume : Many functional materials are traditionally synthesized by slow reaction processes that are energy and time consuming. In the present world there is strong demand on development of modern materials and materials processing methods that could offer rapid reaction rates, energy efficiency and be environmentally safe. Here we report application of newly developed Electric Discharge Assisted Mechanical Milling (EDAMM)  technique for generation of rapid chemical reactions in plasma environment. Electro-mechano-chemical processing of solids is a new and exciting materials processing technique which combines the attributes of conventional mechanical milling with all effects generated by electric discharges. It is demonstrated that Electro-mechano-chemical method can be used to process wide range of materials and synthesize a range of functional materials in a matter of minutes, rather than days. In this study we show application of this method in reduction of oxides, generation of replacement reactions, solubility of nitrogen and hydrogen in metals and non-metals, reactions between carbon and metals, and synthesis of complex oxides from simple oxides or metals. Also the effect of AC and DC plasma on reaction rates will be presented and discussed. Obtained results will be compared and contrast with conventional processing methods such as sol-gel reactions, solid state reactions, mechanical alloying and mechano-chemical approaches that have been used to create reactions between species.  Nature, 419,(2002)147-151
Authors : Malgorzata Lewandowska, Piotr Bazarnik, Marta Lipińska, Ewa Ura-Bińczyk
Affiliations : Warsaw University of Technology Faculty of Materials Science and Engineering
Resume : Nanostructured materials are characterized by grains ranging in size from 1 100 nm and as a result high surface area of grain boundaries. Grain refinement down to nanometre scale offers a great increase in mechanical strength such as yield strength or hardness according to Hall-Petch relationship. However, the effect of reduced grain size on the corrosion resistance is not yet well understood. Due to high volume fraction of intercrystalline regions, they possess a great concentration of defects which increases reactivity and diffusivity. In addition, nanostructure is chemically more homogenous comparing to conventional microstructure, which can decrease the role of corrosion microcells in the electrochemical processes. In this study, the corrosion resistance of aluminium alloys with various grain size and precipitation state was investigated. The measurements were performed in 0.1M NaCl. The potentiodynamic polarization measurements showed that nanocrystalline sample has lower corrosion potential and lower corrosion current compared to microcrystalline one. The observations of surface morphology after immersion in 0.1M NaCl revealed the galvanic corrosion related to the presence of intermetallic particles. For microcrystalline sample, the intergranular corrosion attack was observed. The special attention has been paid on the role of grain boundary misorientation angle and second phase particles.
Authors : L.L. Patera (1,2), G. Prandini (1), V. Carnevali (1,3), C. Africh (2), G. Comelli (1,2), M. Peressi (1)
Affiliations : (1) University of Trieste, Department of Physics, Trieste (Italy); (2) IOM-CNR TASC Laboratory, Trieste (Italy); (3) University of Milan, Department of Physics, Milan (Italy)
Resume : Graphene is a material with outstanding physical, chemical and electronic properties which are relevant to several technological applications, including catalysis. In fact, although perfect graphene is chemical inert, morphological defects may strongly enhance its chemical activity. In the present work we focus on structural defects in graphene epitaxially grown on Ni(111), mainly carbon vacancies partially filled by nickel adatoms. By combining high resolution scanning tunnelling microscopy images and ab-initio calculations, we identify and characterise the structural and electronic properties of the most common defects and, as a preliminary study, we investigate their interaction with small molecules of environmental interest.
Authors : C. DUrso1, C. Oldani2, V. Baglio1, , L. Merlo2, A.S. Aricò1
Affiliations : 1 Istituto di Tecnologie Avanzate per lEnergia Nicola Giordano (CNR), via Salita S. Lucia sopra Contesse, 5 - 98126 Messina, Italy; 2Solvay Specialty Polymers Italy S.p.A., Viale Lombardia 20, Bollate (MI), Italy
Resume : A radical scavenger based on Ce-oxide supported on sulfonated silica was synthesized by a simple method and physico-chemically characterized to investigate the structure and morphology. The material was introduced in ePTFE reinforced membranes prepared starting from suitable Aquivion® PFSA dispersions. The aim is to mitigate the peroxy radicals attack to the polymeric membrane under fuel cell operating conditions. The influence of this hydrogen peroxide decomposition catalyst on the membrane durability was investigated ex-situ by using a Fentons test and under OCV accelerated stress test in a real fuel cell. These membranes show much longer lifetime in Accelerated Stress Tests (AST) and reduced fluoride release in Fentons tests than the radical scavenger-free membrane without any loss in electrochemical performance. These results confirm the stability of the modified membranes and the excellent activity of the composite scavenger in mitigating the polymer electrolyte degradation. Furthermore, the silica supported scavenger is more stable in terms of leaching behaviour than a membrane containing unanchored Ce(III) ions.
Authors : Mikito Ueda
Affiliations : Faculty of Engineering, Hokkaido University
Resume : Al alloys are electrodeposited from chloroaluminate molten salt or ionic liquid containing AlCl3. In this presentation, I report electrodeposition of Al-Pt alloys, Al-Sn alloys, and Al-Ta alloys. To form Al-Pt alloys, molten salt electrolysis was carried out in an AlCl3-NaCl-KCl molten salt containing PtCl2 at 448 K. The voltammogram showed cathodic reduction of Pt ions to start at a potential of 1.4 V vs. Al/Al(III) in the molten salt. Deposition of pure Pt was possible at 1.2 V and there was co-deposition of Al and Pt at potentials more negative than 1.0 V. The co-deposit was a mixture of intermetallic compounds of AlPt2 or AlPt3. Electrodeposition of Al-Sn alloys was performed in the AlCl3-NaCl-KCl molten salt containing SnCl2 at 423 K or 1-ethyl-3-methyl imidazolium chloride (EMIC)- AlCl3 ionic liquid containing SnCl2 at 303 K. Co-deposition of Al and Sn occurred at potentials more negative than 0.1 V. In comparison of morphology of electrodeposits, Al-Sn electrodeposit formed in ionic liquid became more fine particles than that formed in molten salt. In the structural observations of Al-Sn alloys, an alternate stacked structure of Al and Sn is obtained in the molten salt. Al-Ta alloys was electrodeposited in the AlCl3-NaCl-KCl molten salt containing TaCl5 at 423 K. In the voltammogram, 2 step cathodic reduction of Ta ions occurred at potential of 0.7 and 0.45 V in the molten salt. When Ta concentration in the electrodeposit increased, size of Al-Ta electrodeposit d
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Short Communications : Marcin Pisarek
Authors : M. Gioti1, C. I. Chaidou1, D. Kokkinos1, C. Pitsalidis1, C. Polyzoidis1, A.K. Andreopoulou2,3, E. Mparmpoutsis2, J.K. Kallitsis2,3, S. Logothetidis1
Affiliations : 1 Laboratory for Thin Films-Nanosystems and Nanometrology (LTFN), Physics Department, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece; 2 Department of Chemistry, University of Patras, University Campus, Rio-Patras GR26504, Greece; 3 Foundation for Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Platani Str., Patras GR26504, Greece
Resume : New synthesized anthracene-based and carbazole-based polymers as well as commercially available polymers such as polyfluorenes and polyphenylene vinylenes were applied as emitting materials in organic light-emitting diode (OLED) devices. Initially, spin coating and subsequently printing processes were used for the fabrication of the polymer thin films and the final devices either in rigid or flexible form. The photoluminescence (PL) of the polymeric films were evaluated by Fluorescence Spectroscopy revealing the characteristic emission of each material. The optical properties of the polymers were investigated by NIR-Vis-far UV Spectroscopic Ellipsometry. The accurate determination of the thickness and the optical constants (refractive index, dielectric function and absorption coefficient as a function of wavelength) were derived. Furthermore, quantum yield measurements, brightness, chromaticity and current densityvoltage characteristics of the devices were obtained. A strong correlation between the optical properties, the thickness and the devices performance was established since external quantum efficiency of electroluminescence also depends on the optical interference of the beams of emitted light multiply reflected from the layer interfaces. This provides substantial insights into the final design of the optimum final multi-layer structure of the OLEDs whereas the potentiality for the development of flexible OLEDs with bigger active area devices is demonstrated.
Functional Materials/Nanomaterials: 2 : Hiroki Habazaki
Authors : Markus Niederberger
Affiliations : Laboratory for Multifunctional Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich, Switzerland
Resume : Nanostructures including nanoparticles, nanowires and nanosheets are the ideal building blocks for the bottom-up fabrication of functional materials. They offer an immense variety of interesting properties, which not only depend on the composition, but also on the crystal structure, the particle size and shape and on the surface chemistry. Accordingly, potential synthesis routes have to provide full control over all these parameters. In addition, for most applications the nanoparticles have to be assembled and processed into useful geometries, architectures and bodies, and for this purpose, the surface properties of the nanoparticles have to be tailored carefully. The talk will cover the synthesis of metal oxide nanoparticles with different morphologies by nonaqueous sol-gel chemistry and their use as building blocks for the fabrication of 2- and 3-dimensional architectures. Fine-tuning of the surface chemistry of the nanoparticles makes it possible to self-assemble them over several length scales from the nanometer to the centimeter range . For specific applications the nanoparticles can also be processed into thin films. Finally, we will show how such a bottom-up approach using preformed building blocks can be extended to the fabrication of macroscopic metal sponge monoliths .  Metal Oxide Particles in Materials Science: Addressing All Length Scales, D. Koziej, A. Lauria, M. Niederberger, Adv. Mater. 2014, 26, 235-257.  Wet-Chemical Preparation of Copper Foam
Authors : Dickon H.L. Ng (1), Jia Li (2)
Affiliations : (1) Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China; (2) School of Material Science and Engineering, University of Jinan, Jinan, China
Resume : Magnetic hollow fibers containing ZnFe2O4 nano-crystallites were fabricated by bio-templating. In sample preparation, kapok fibers were submerged in a mixture of Zn(NO3)2 and Fe(NO3)2. The infiltrated kapok fibers were dried and heat-treated at high temperature in ambient. Characterization showed that the appearance of the as-prepared sample resembled to those of the original kapok fibers. However, they were fully covered with ZnFe2O4 nano-crystallites (size of 30 to 50 nm), and with pores ranging from 2 to 10 nm. The adsorption kinetics and thermodynamics of the organic dye (acid fuchsin) molecules attached onto the ZnFe2O4 fibers were investigated. The adsorption was spontaneous and exothermic and the process could be well-described by the Langmuir model, and the pseudo second order kinetics model as well. The maximum adsorption capacity of these hollow fibers for acid fuchsin was determined to be 150.4 mg/g. Electrostatics and specific interactions between the dye molecules and the organic groups on the fiber surface were considered to be the drive of adsorption. The hollow fibers also exhibited strong ferrimagnetic behavior. This favored their high-efficient magnetic separation from waste water under applied magnetic field after dye adsorption. The fabrication route of the magnetic ZnFe2O4 hollow fibers by using kapok as bio-template is facile. In adsorbing organic dyes during water treatment, they appear effective and user-friendly.
Authors : Micael Alonso Frank1,2, Christian Meltzer3, Björn Braunschweig3, Wolfgang Peukert3, Aldo. R. Boccaccini2 and Sannakaisa Virtanen1
Affiliations : 1-Institute of Surface Science and Corrosion, University of Erlangen-Nuremberg, Germany 2-Institute of Biomaterials, University of Erlangen-Nuremberg, Germany 3-Institute of Particle Technology, University of Erlangen-Nuremberg, Germany
Resume : The interactions between organic molecules and surfaces of steels were studied. Various organic acids were used with different chain lengths and different chemical bonding. Two materials were used as substrates, stainless steel 316L and carbon steel N80. These two materials were chosen regarding their opposite corrosion resistance: stainless steel 316L has a high resistance and a wide range of applications, whereas carbon steel N80, which is used for instance in petroleum industries, shows a low corrosion resistance. Surface binding was created and the surface energy was decreased, which induced a decrease in the wettability. In order to analyze the homogeneity of the coatings as a function of the immersion time, concentration, chain length and the chemical bond between the molecules and the surface, sum frequency generation spectroscopy was used. In a previous study for this kind of organic coating, the interaction between surface roughness and surface energy according to the Cassie-Baxter model led to superhydrophobic surfaces with a contact angle above 150°. We also examined the correlation between the immersion time, concentration, chain length and chemical binding of the molecules and the corrosion resistance and wettability. Electrochemical investigations revealed a shift of the corrosion potential values into the positive direction, a decrease of the corrosion current density, this correlating with an improvement in the hydrophobicity of the samples.
Authors : Andrei Ionut Mardare, Jan Philipp Kollender, Martina Hafner, Achim Walter Hassel
Affiliations : Christian Doppler Laboratory for Combinatorial oxide chemistry at the Institute for Chemical Technology of Inorganic Materials Johannes Kepler University Linz, 4040, Linz, Austria; CEST Competence Centre for Electrochemical Surface Technology Viktor Kaplan Strasse 2, 2700, Wiener Neustadt, Austria
Resume : Scanning droplet cell microscopy (SDCM) recently found applications in fields with implications beyond pure electrochemistry. Due to a new special tip design allowing for stationary or flowing electrolyte conditions, a high reproducibility of the wetted area is achieved which makes the SDCM a preferred tool for local corrosion testing on metallic surfaces as well as for performing electrochemical screening of thin film combinatorial libraries. The electrochemical behavior of Hf-Ta thin film alloys deposited by co-sputtering in a wide compositional range (21 to 91 at.% Ta) was investigated. The transition from hexagonal Hf to tetragonal Ta along the compositional spread occurs through an amorphisation region where Hf-Ta metallic glasses were evidenced. The properties of anodic oxides grown on Hf-Ta alloys were mapped along the compositional gradient. Remarkable dielectric properties of the mixed Hf-Ta oxides were identified with direct applications in electronics as high-k materials. The use of highly sensitive downstream analytics (inductively-coupled plasma mass spectrometer) coupled to a flow-type SDCM allowed a careful quantitative study of the corrosion behavior of the Hf-Ta alloys. The corrosion rates dependence on the Hf-Ta composition are presented for the entire compositional spread analyzed. This is highly relevant for challenging applications such as nuclear fuel element cladding, liquid alkali metal containment or bio-medical applications (e.g. orthopedic implants).
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