A first-principles study of CO oxidation by surface oxygen on Pt-incorporated perovskite catalyst (CaPtxTi1−xO3)

Abstract

In the present work, we investigated the structural and catalytic properties of a prototype system Pt-doped CaTiO₃ by means of first principles calculations. We paid particular attention to the aggregation and penetration of Pt on different surfaces of CaTiO₃, and subsequent CO oxidation by surface oxygen atoms on Pt-doped CaTiO₃. Our calculations indicate that CO oxidation can potentially take place when Pt is doped on the first layer of CaTiO₃(001). The activation barriers are calculated to be 0.20–0.45 eV. The possibly induced O vacancy on the surface will produce a magnetic behavior by breaking the spin density symmetry due to one Pt–O bond cleavage. Our study is expected to provide an insight into the catalytic behavior of Pt ions in Pt-doped perovskite toward the oxidation of exhaust gas.