Publications associées à Oxyde de tantale(V)

Morphology of Nanostructured Tantalum Oxide Controls Stem Cell Differentiation and Improves Corrosion Behavior

Tantalum is receiving increasing attention in the biomedical field due to its biocompatible nature and superior mechanical properties. However, the bioinert nature of tantalum still poses a challenge and limits its integration into the bone tissue. To addr ...

Amer Chemical Soc2023

Enhanced radio-frequency performance of niobium films on copper substrates deposited by high power impulse magnetron sputtering

Fabio Avino

We present a study of radio frequency properties of niobium films deposited on copper by two different approaches based on High Power Impulse Magnetron Sputtering, namely with a DC voltage biased substrate and with bipolar target voltage. Such approaches e ...

2022

Strong coloration of nanoporous tungsten oxides by in-vacuo lithiation for all-solid-state electrochromic devices

Andreas Schueler, Anna Krammer, Maxime Lagier, Olivia Valérie Charlotte Bouvard, Luc Burnier

Electrochromic windows allow for an improved management of solar heat gains in buildings and enhanced visual comfort of building users. All-solid-state electrochromic devices can be especially durable. During their fabrication lithium has to be inserted, p ...

ELSEVIER SCIENCE SA2021

Color neutral nanocomposite nickel-tantalum oxide for electrochromic windows

Andreas Schueler, Josef Andreas Schuler, Olivia Valérie Charlotte Bouvard

Electrochromic windows can darken on demand to limit the solar gains entering a building to reduce the risk of overheating, while preserving the view towards the exterior. Yet, the switching speed and contrast as well as the durability of commercial produc ...

IOP2019

Coatings with tailored electronic and optical properties for advanced glazing

Olivia Valérie Charlotte Bouvard

Modern envelope glazing relies on nanoscale coatings to meet a range of specific needs. Low emissivity coatings can improve the thermal performance of glazing thanks to a thin metallic film. However, the conductive nature of this layer leads to an attenuat ...

EPFL2019

Electronic Structures and Catalytic Activities of Niobium Oxides as Electrocatalysts in Liquid-Junction Photovoltaic Devices

Ulf Anders Hagfeldt, Sheng Meng, Sining Yun, Hang Liu

Two types of nanosized niobium oxides and their composites, pseudohexagonal Nb2O5 (TT-Nb2O5), monoclinic NbO2 (M-NbO2), and the coexistence of TT-Nb2O5 and M-NbO2 (TT-Nb2O5/M-NbO2), are successfully synthesized through the urea-metal chloride route, and th ...

WILEY-V C H VERLAG GMBH2019

Experiments and modelling for glow discharge plasmas applied to niobium sputter deposition in superconducting radiofrequency cavities

Thibaut François Hugo Richard

Thin film coatings are ubiquitous in modern daily lives, from the semi-conductor industry to aesthetic applications, and rely on the modification of a given material to enhance its surface properties. At CERN (European Organization for Nuclear Research), t ...

EPFL2019

Highly efficient dye-sensitized solar cells achieved through using Pt-free Nb2O5/C composite counter electrode and iodide-free redox couples

Ulf Anders Hagfeldt, Weiwei Zhang, Wenyan Li

To improve the catalytic activity of Nb2O5, a composite Nb2O5/C (Nb2O5 imbedded in carbon support) is synthesized with a simple in situ method and then introduced the composite into dye-sensitized solar cells (DSCs) as a counter electrode (CE) catalyst. Ba ...

Elsevier Science Bv2016

High-Temperature Ammonolysis of Thin Film Ta2O5 Photoanodes: Evolution of Structural, Optical, and Photoelectrochemical Properties

Ali Dabirian

Tantalum nitride (Ta3N5) and oxynitride (TaON) are promising materials for photoelectrochemical (PEC) water splitting due to near-ideal band gaps and band edge positions. However, the high-temperature ammonolysis process that is usually used to make these ...

Amer Chemical Soc2015

Evaluation of niobium dimethylamino-ethoxide for chemical vapour deposition of niobium oxide thin films

Patrik Willi Hoffmann, Ali Dabirian, Yury Kuzminykh, Estelle Wagner, Giacomo Benvenuti

Chemical vapour deposition (CVD) processes depend on the availability of suitable precursors. Precursors that deliver a stable vapour pressure are favourable in classical CVD processes, as they ensure process reproducibility. In high vacuum CVD (HV-CVD) pr ...

Elsevier2014

Understanding the Role of Underlayers and Overlayers in Thin Film Hematite Photoanodes

Michael Graetzel, Stanley David Tilley, Ludmilla Steier

Recent research on photoanodes for photoelectrochemical water splitting has introduced the concept of under-and overlayers for the activation of ultrathin hematite films. Their effects on the photocatalytic behavior were clearly shown; however, the mechani ...

Wiley-V C H Verlag Gmbh2014

The Influence of the Ammonolysis Temperature on the Photocatalytic Activity of beta-TaON

Michael Graetzel, Takashi Hisatomi

Phase-pure tantalum oxynitride (beta-TaON) powders were synthesized by thermal ammonolysis of Ta2O5 powders. X-ray diffraction revealed an enlargement of the unit cell and an increase of the crystallite size with increasing ammonolysis temperature. Scannin ...

Hindawi Publishing Corporation2013

Post-irradiation analysis of the tantalum container of an ISOLDE LBE target

CERN-ISOLDE operates a range of oxides, carbides, refractory metal foils and liquid metal targets for the production of radioactive ion beams. Following irradiation with a pulsed beam of 1 GeV and 1.4 GeV protons at temperatures reaching 600 degrees C, the ...

Elsevier Science Bv2012

Combinatorial Discovery and Optimization of Amorphous HfO2-Nb2O5 Mixture with Improved Transparency

Paul Muralt, Patrik Willi Hoffmann, Silviu Cosmin Sandu, Ali Dabirian, Yury Kuzminykh, Scott Harada, Estelle Wagner, Giacomo Benvenuti, Bamdad Afra

Combinatorial high vacuum chemical vapor deposition (HV-CVD) of mixed HfO2-Nb2O5 thin films has been demonstrated to yield amorphous layers at substrate temperatures where individually deposited pure HfO2 and Nb2O5 films are polycrystalline. Spectroscopic ...

Electrochemical Society2010

Plate for matrix-assisted laser desorption ionization mass spectrometry, comprises electroconductive substrate covered with sintered nanoparticles, deposited as array of spots, for supporting ionization of sorbed sample molecules

Hubert Girault, Niels Erik Lion, Christophe Roussel, Liang Qiao, Michel Prudent, Jingjing Wan

NOVELTY - A plate comprises an electroconductive substrate (1) at least partially covered with sintered nanoparticles (2), deposited as an array of individual spots, for use as a sorbing phase for a sample, and for supporting ionization of sorbed sample mo ...

2009

Fibronectin adsorption on tantalum: The influence of nanoroughness

Kristian Rechendorff

The complex mechanisms of protein adsorption at the solid-liquid interface is of great importance in many research areas, including protein purification, biocompatibility of medical implants, biosensing, and biofouling. The protein adsorption process depen ...

2008

Electrode and chemical reactions during electrodeposition of tantalum products in CsCl melt

Alla Arakcheeva

This work was accomplished in the context of systematic examination of a role played by electrolyte cation composition in electroreduction processes. The electrochemical behaviour of molten salts systems where CsCl was used as solvent for potassium and cae ...

2006

Pulsed laser deposition of (SrBa)Nb2O6 thin films and their properties

Anna Infortuna

Strontium barium niobate (SrxBa1-xNb2O6, shortly SBN) is a solid solution system with tetragonal tungsten bronze crystal structure. It exhibits a ferroelectric phase with only one polar axis and a transition temperature depending on the Sr/Ba ratio. This t ...

EPFL2005