Coadsorption of gold with chlorine on CeO2 (111) surfaces: A first principles study**Project supported by the National Natural Science Foundation of China (Grant Nos. 11174070, 51401078, and 11147006), the China Postdoctoral Science Foundation (Grant No. 2012M521399), the Postdoctoral Research Sponsorship in Henan Province, China (Grant No. 2011038), and the Foundation for the Key Young Teachers of Henan Normal University and

Abstract

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.