▎ 摘　　要

Graphene and its derivatives are attractive for electrocatalytical application in dye-sensitized solar cells because of their unique structures and electronic properties. By means of density functional theory calculations, the mechanism of triiodide reduction reaction on nitrogendoped graphene (NDG) was studied in acetonitrile environment. The computations demonstrated that the rate-determining step was the ability of NDG to release electrons to active iodine atoms. According to the calculation, the optimal NDG was designed with nitrogen contents of 4.0 % graphite N and 3.0 % pyridinic N approximately. In order to precisely distinguish these two nitrogen species in the optimal NDG, we proposed the chemical shift of N-15 NMR of nitrogen doped in graphene provided guidance for the experiments.