IRAS study of carbon monoxide adsorption on sulfur-modified molybdenum (110) surfaces

Abstract

Infrared reflection absorption spectroscopy (IRAS) was used to study the adsorption of CO on a S-modified Mo(110) surface. As the surface S coverage is increased to 0.5 ML, the sulfur overlayer structure changes from p(2x2) to c(2x2). These changes can be observed in the IRAS spectra of adsorbed CO. In addition, it was noted that in the p(2x2)S overlayer sulfur acted mainly as a site blocker, whereas in the c(2x2)S overlayer electron-withdrawing effects became apparent. Finally, the dissociative adsorption of CO was seen to occur on both clean Mo(110) and p(2x2)S/Mo(110) but not on c(2x2)S/Mo(110). 31 refs., 10 figs.