1.2x10(exp -5) Pa の酸素、エチレンに接触しているCsおよびRe添加Ag触媒表面のin situ XPS分析

Abstract

Dynamic behaviors of electronic charges and surface concentrations of Cs, Re, and O on self-supporting disc surfaces of Cs and Re-doped Ag powder catalyst during the operation of O2- and C2H4-jet were measured at 1.2x10(exp -5) Pa and 483 K using a conventional XPS. Exposure of the disc surface to O2-jet caused slight oxidations of Cs and Re, mild migrations of Cs and Re into bulk phase, and an increase of surface oxygen concentration with exposure time, while the exposure to C2H4-jet resulted in a slight reduction of Cs and a decrease of surface oxygen concentration. Deconvolution of O1s spectra resulted in five core spectra, of which the composition ratio changed drastically with exposure time Furthermore, relationships between the parameters mentioned above and pressure of active gases in contact with the disc surface were discussed.