Eu-Doped BaTiO3 Powder and Film from Sol-Gel Process with Polyvinylpyrrolidone Additive

Transparent BaTiO3:Eu3+ films were prepared via a sol-gel method and dip-coating technique, using barium acetate, titanium butoxide, and polyvinylpyrrolidone (PVP) as modifier viscosity. BaTiO3:Eu3+ films ~500 nm thick, crystallized after thermal treatment at 700 ºC. The powders revealed spherical and rod shape morphology. The optical quality of films showed a predominant band at 615 nm under 250 nm excitation. A preliminary luminescent test provided the properties of the Eu3+ doped BaTiO3

PREPARATION DE S RBI 2NB 2O 9 PAR VOIE SOL-GEL (CRISTALLISATION DES POUDRES ET COUCHES MINCES EPITAXIEES)

LIMOGES-BU Sciences (870852109) / SudocSudocFranceF

Préparation de SrBi2Nb2O9 par voie sol-gel (cristallisation des poudres et couches minces épitaxiées)

LIMOGES-BU Sciences (870852109) / SudocSudocFranceF

Structure and morphological study of nanometer W and W3O thin films

International audienceIn this paper, the structure of nanometer tungsten thin films has been correlated to their surface morphology. Films have been deposited by RF-sputtering at a working pressure of 0.5 Pa and with a power density of 1.18 W/cm 2. Two phases with different morphology has been observed : W 3 O with a nanograins structure is present in the first step of the tungsten growth; and, when the thickness is increased, a pure tungsten Wolfram phase (W) with a lamellar structure appears. We demonstrate that W 3 O is related to a pollution of the target surface between two growth runs. We succeed to suppress this phase and to obtain pure tungsten Wolfram nanolayer, in order to realize [W/WO 3 ] n multilayer

Microstructural and mechanical investigations of tungsten carbide films deposited by reactive RF sputtering

Symposium on Protective Coatings and Thin Films held at the E-MRS Spring Meeting, Strasbourg, FRANCE, MAY 31, 2004-JUN 03, 2005International audienceTungsten carbide thin films were deposited on (100) Si single crystal substrates by reactive RF sputtering from a tungsten target in Ar-CH4 mixture. Under 1% of methane, the formation of a mixture of nanocrystalline WC1-x presenting a partial (200) texture and W2C phases was observed. The film deposited under 2% of CH4 shows a maximum hardness of 22 GPa (a value comparable to the bulk WC reference material), these coatings also exhibit the lowest friction coefficient of 0.1. For coatings performed with CH4 percentage higher than 3%, a progressive amorphization of the layers was observed. At 5% of CH4 concentration, the films become essentially amorphous. Simultaneously the hardness decreases continuously to achieve a minimum value of 13 GPa. (c) 2005 Elsevier B.V. All rights reserved

Micromechanical Properties of Nanometer-Thick Layers of Implanted Alumina

International audienc

Determination of optimum extinction wavelength for paracetamol removal through energy efficient thin film reactor

Paracetamol (PAM) mineralization through nano-composite thin film (TF) based photocatalytic system was investigated under variable operational conditions. The experiments were conducted using a non stirred flow through coated tubular quartz reactor (TQR). Elimination of energy demand arising from stirring and aeration through the developed TF reactor configuration was also among the main research interests. Ag-doped Si-TiO2 TFs were grown on Si-decorated inner surface of the TQR using sol-gel dip coating technique. The fabricated TF was characterized by SEM-EDS, TEM, AFM, XPS and UVvis spectroscopy methods. TF-based PAM mineralization kinetics were observed for both UVvis and UV wavelengths using pure, Si-Ti and Ag-doped Si-TiO2 TF(s). The direct and indirect optical ban gap energies (BGE) for the Ag doped Si-TiO2 TF were estimated to be 2.56 eV and 2.86 eV respectively. While no visible light activity was observed for pure TiO2 TF, Ag-doped Si-TiO2 TF exhibited significant PAM degradation activity for lambda > 400 nm with a k(obs) value of 2.1 +/- 0.1 10(-3) min(-1). In addition to known phenolic and carboxylated intermediates, UVvis spectroscopy, HPLC-MS and UPLC-MS/MS measurements indicated alpha-cyano-4-hydroxicinnamic acid (alpha PHC) formation as a result of photo-addition reactions under UV C irradiation. Experimental results also indicated that alpha PHC blocks h(+)/e(-) formation completely. Paracetamol could be degraded economically under UV B irradiation through the fabricated TF reactor without stirring, aeration or adding external electron acceptors. (C) 2016 Elsevier B.V. All rights reserved.Scientific and Technological Research Council of Turkey TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [111Y209]; Food Antioxidants Measurement & Application CenterThis work is partially funded by The Scientific and Technological Research Council of Turkey TUBITAK (Project 111Y209). The authors express their gratitude to Food Antioxidants Measurement & Application Center for the support given to the projects