Influence of Cl substitution on the electronic structure and catalytic activity of ceria

Cl-containing cerium dioxide (CeO2) catalysts have been found to exhibit unique catalytic activities. In the present work, using density functional theory calculations with the inclusion of on-site Coulomb correction, we systematically studied the effect of Cl on the physicochemical properties of CeO2 surfaces by substituting one subsurface O with Cl. The calculated results show that substituting an O atom with a Cl atom results in structural distortion and the reduction of one surface Ce4+ cation to Ce3+. The protruding Ce3+ cation greatly improves the adsorption energy of O-2 to produce an active O-2 (-) species, and maintains the catalytic oxidation cycle of CO on CeO2(110). These results may help us obtain a better understanding of Cl-ceria interacting systems and provide some guidance for the design of effective CeO2-based catalysts.