Coadsorption of gold with chlorine on CeO₂ (111) surfaces: A first principles study

To investigate the effects of chlorine on the Au/ceria catalysts, the adsorption of gold or chlorine and their coadsorpiton on the stoichiometric and partially reduced CeO₂ (111) surfaces are studied from the first principles. It is found that the adsorption of Au is significantly enhanced by the chlorine preadsorption on the stoichiometric CeO₂ (111) surface; while on the partially reduced CeO₂ (111) surface, the preadsorbed chlorine inhabits the oxygen vacancy (which is the preferred adsorption site for gold), leading to a CeOCl phase and the dramatical weakening of the Au adsorption. Therefore, chlorine on the CeO₂ (111) surface can affect the Au adsorption thus the activity of the Au/CeO₂ catalyst.