The Interaction of Ethylene with Surface Carbonate and Hydroxide Intermediates on Silver
نویسندگان
چکیده
The surface chemistry of the intermediates formed from the adsorption of CO, and Hz0 on an oxygen-atom-covered Ag( 110) surface was investigated with surface spectroscopic techniques. Carbon dioxide complexed with adsorbed oxygen atoms to form a surface carbonate intermediate, and the associative adsorption of water led to the formation of surface hydroxides. COz adsorption on the oxygen atom covered Ag( 110) surface produced two-dimensional rearrangements of the surface species. Ethylene was not found to react with COzads and OHad, below room temperature, but did exhibit some reactivity toward COsads at room temperature. This investigation showed that the formation of COaads and OHad, on the silver surface are responsible for the inhibiting effects of COr and Hz0 during ethylene oxidation over silver catalysts.
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