First-Principles Study on the Effects of Zr Dopant on the CO Adsorption on Ceria

Abstract

With use of the first-principles density functional theory with the inclusion of the on-site Coulomb interaction of the Ce4f electrons (DFT+ U ) method, the adsorption of CO on the (110) surface of a stoichiometric Ce 0.75 Zr 0.25 O 2 system is studied systematically. It is found that, (1) in addition to the carbonate-like CO 3 structures, there exists a new adsorption species (a bent CO 2 − structure) on the Ce 0.75 Zr 0.25 O 2 (110) surface, and (2) the Zr-dopant can enhance the adsorption of CO and improve the CO oxidation process on the ceria surface by promoting the desorption of CO 2 .