Structural and catalytic properties of ultra-dispersed silver powders prepared by metal evaporation with high-power electron beam. 2. Catalytic properties in ethylene epoxidation with molecular oxygen

Abstract

Catalytic properties of ultra-dispersed silver powders synthesized via electron-beam evaporation of silver in Ar, N 2 or He were studied in the ethylene epoxidation. The highest selectivity was observed for a Ag(Ar) sample. It was associated with the formation on the silver surface of specific oxide-like species formed in the presence of argon. The nature of these species was also studied with UV-vis and XPS spectroscopy as well as with TPD.