Horwat, David , Dehmas, Moukrane , Gutierrez, Alejandro , Pierson, Jean-Francois , Anders, Andre , Soldera, Flavio , ENDRINO ARMENTEROS, JOSÉ LUIS
Si
Chem. Mater.
Article
Científica
8.238
4.181
10/07/2012
000306200700003
2-s2.0-84863697334
An efficient, low cost synthesis of sodium platinum bronze Na xPt 3O 4 was investigated. PtO y films were deposited on silicon and SLG slides. Chemical and structural evolutions of the films upon annealing in air were probed by X-ray absorption near edge structure (XANES), X-ray diffraction (XRD), and high resolution transmission electron microscopy (HRTEM). An average oxidation state of 3.2 is derived from the XANES signal of the as-deposited films, corresponding to stoichiometry PtO 1.6. This reflects the fact that sputter-deposited PtO y films are mixtures of PtO and PtO 2 phases at the nanometer scale. When using a silicon substrate, further oxidation of the film is observed up to an average oxidation state of 3.6 upon annealing at 300°C, corresponding to a mixture of 80 mol % PtO 2 and 20 mol % PtO. XRD analyses indicated that the film remained nanocrystalline during the process.
thin films; platinum; oxide; soft synthesis; sodium