▎ 摘　　要

The stable configurations, electronic structures and catalytic activities of single-atom metal catalyst anchored silicon-doped graphene sheets (3Si-graphene-M, M = Ni and Pd) are investigated by using density functional theory calculations. Firstly, the adsorption stability and electronic property of different gas reactants (O-2, CO, 2CO, CO/O-2) on 3Si-graphene-M substrates are comparably analysed. It is found that the coadsorption of O-2/CO or 2CO molecules is more stable than that of the isolated O-2 or CO molecule. Meanwhile, the adsorbed species on 3Si-graphene-Ni sheet are more stable than those on the 3Si-graphene-Pd sheet. Secondly, the possible CO oxidation reactions on the 3Si-graphene-M are investigated through Eley-Rideal (ER), Langmuir-Hinshelwood (LH) and new termolecular Eley-Rideal (TER) mechanisms. Compared with the LH and TER mechanisms, the interaction between 2CO and O-2 molecules (O-2 + CO -> CO3, CO3 + CO -> 2CO(2)) through ER reactions (< 0.2 eV) are an energetically more favourable. These results provide important reference for understanding the catalytic mechanism for CO oxidation on graphene-based catalyst.