▎ 摘　　要

Based on the density functional theory calculations, the formation geometry, electronic properties, and catalytic activity of metal impurities in divacancy graphene (M-DG, M = Mo, Fe, Co, and Ni) were systematically investigated. It has been found that the reactive gases have different stabilities on M-DG substrates, and these quite stable substrates exhibit high catalytic activity for CO oxidation by comparing the traditional Eley-Rideal (ER) and Langmuir-Hinshelwood (LH), as well as the new termolecular ER (TER) mechanisms. For the Co-DG substrate, the coadsorption of O-2 and CO as a starting step is an energetically more favorable process, whereas the dissociation reaction of O-2 molecules on Mo-DG substrate has a much smaller energy barrier, and the generation of atomic oxygen is active for CO oxidation. These results indicate that the varied adsorption behaviors of reactive gases on M-DG substrates can determine the catalytic pathways and energy barriers, which give us insight into the surface reactivity of graphene-metal composite catalysis in energy-related devices.