LAUSR

Abstract It is well-known that the promoter can enhance the selectivity to ethylene oxide (EO) of Ag catalyzed ethylene epoxidation. However, the selectivity enhancement on different crystal planes of Ag catalysts derived from various promoters is still indistinct. In this work, in order to get an atomistic insight into the synergistic effect between crystal planes and promoters on catalytic performance of Ag catalysts, we study ethylene epoxidation on Ag (1 1 1), (1 1 0) and (1 0 0) surfaces with the promoters of Re, Cs and Cu by density functional theory calculations. It is found that selectivity enhancement introduced by the promoters on Ag (1 1 1) surfaces is more obvious compared with that on Ag (1 1 0) and (1 0 0) surfaces. The sequence of EO selectivity on Ag (1 1 0) surfaces is Re