▎ 摘　　要

Single transition metal (TM) atom-doped graphene has been experimentally proved to be effective for catalyzing electrochemical reactions. However, oxygen reduction reactions (ORR) exhibit poor catalytic performance due to the high binding energy between the active site and the adsorbed species. Here, we propose a feasible strategy to modulate the binding strength of the oxygenated species on the graphitic nanosheet by introducing metal substrate gating. Density functional theory calculation results reveal the remarkable enhancement of ORR performance with the confinement of the Ni(111) surface, and the overpotentials for six different transition metal (TM) atom-doped pentagonloctagonlpentagon (51 815) graphene (TM@5 vertical bar 8 vertical bar 5G) systems on the Ni(111) surface can be significantly reduced, particularly for the case of Co@5 vertical bar 8 vertical bar 5G (from 0.98 to 0.33 V). This is mainly attributed to the electron coupling between the metal substrate and TM@5 vertical bar 8 vertical bar 5G. Moreover, the catalytic activity can be well modulated by adjusting d-band center of TM atoms, leading to an ideal energy level of the d-band center for TM@5 vertical bar 8 vertical bar 5G on the Ni substrate (-1.48 eV), at which ORB, can achieve the highest performance.