Oxidation behavior of PdSi compounds

The room temperature oxidation of PdSi, Pd2Si and Pd4Si has been studied using X-ray photoelectron spectroscopy (X-ray photoemission spectroscopy or electron spectroscopy for chemical analysis). We find that only silicon atoms in these silicides are oxidized and the oxidation of Pd4Si surfaces is enhanced compared with that of Pd2Si and PdSi, as is evidenced by both a higher silicon oxidation state and thicker oxide films. This behavior is discussed in terms of silicide stability and a spill-over effect where palladium atoms catalyze molecular oxygen dissociation. © 1983.