Computational Investigation of CO Adsorption and Oxidation on Mn/CeO2(111) Surface

The interaction and mechanism for CO oxidation on the Mn/CeO 2 (111) surface have been studied by using periodic density functional theory calculations corrected with the on-site Coulomb interaction via a Hubbard term (DFT + U). It is found that the Mn dopant facilitates oxygen vacancy formation, while the Mn adatoms may restrain oxygen vacancy formation. In addition, physisorbed CO, physisorbed CO 2,and chemisorbed CO (carbonite, CO 2 – ) species are observed on the Mn-doped CeO 2 (111) surface, in contrast, only physisorbed CO is found on the pure CeO 2 (111) surface. The vibrational frequency calculations as well as the calculated adsorption energies are carried to characterize these species. The Mn dopant promotes CO oxidation without any activation energy leading to O vacancy formation and CO 2 desorption. The Bader charge analysis is carried to characterize the oxidation state of Mn ions along the catalytic cycle.