Horwat, D. , Zakharov, D. I. , ENDRINO ARMENTEROS, JOSÉ LUIS, Soldera, F. , Anders, A. , Migot, S. , Karoum, R. , Vernoux, Ph , Pierson, J. F.
Si
Surf. Coat. Technol.
Article
Científica
1.867
1.041
25/07/2011
000293258600037
2-s2.0-79959804067
The chemistry, microstructure, and catalytic activity of thin films incorporating palladium were studied using scanning and transmission electron microscopies, X-ray diffraction, spectrophotometry, 4-point probe and catalytic tests. The films were synthesized using pulsed filtered cathodic arc and magnetron sputter deposition, i.e. techniques far from thermodynamic equilibrium. Catalytic particles were formed by thermally cycling thin films of the Pd-Pt-O system. The evolution and phase formation in such films as a function of temperature were discussed in terms of the stability of PdO and PtO(2) in air. The catalytic efficiency was found to be strongly affected by the chemical composition, with oxidized palladium definitely playing a major role in the combustion of methane. Reactive sputter deposition of thin films in the Pd-Zr-Y-O system allowed us forming microstructures ranging from nanocrystalline zirconia to palladium nanoparticles embedded in a (Zr,Y)(4)Pd(2)O matrix. The sequence of phase formation is put in relation to simple thermodynamic considerations. (C) 2010 Elsevier B.V. All rights reserved.
Noble metal oxides; Palladium; Thin films; Catalysts; Zr(4)Pd(2)O; Physical vapor deposition