In-situ EXAFS analysis of the local environment of Pt particles incorporated in thin films of SnO2 semi-conductor oxide used as gas-sensors

A very fine and homogeneous dispersion of metallic nanoparticles (3-5 nm) inside polycrystalline SnO2 films was carried out by modified CVD co-deposition. It improves the sensitivity and selectivity for reducing gas detection. In order to verify and refine the models which can explain the role of metallic particles in the detection process, the environment of metallic nanoparticles were studied in Pt doped SnO2 thin film by in-situ EXAFS analysis. XANES region of EXAFS spectra were used to study the variation of the local environment and oxidation state as a function of the temperature and atmosphere. (C) 1998 Elsevier Science S.A. All rights reserved.