▎ 摘　　要

The interaction between oxygen molecule (O-2) and metal-doped graphene has always been a heated discussed issue because O-2 plays an important role in the graphene-based gas-storage materials, sensing platforms, and catalysts. In this article, the effect of an external electric field on the interaction between O-2 and Au-doped graphene is studied using density-functional theory (DFT) calculations. The simulations show that O-2 vertically moves away from Au-doped graphene substrate under a positive electric field, whereas under a negative electric field, accompanied by the vertical pushing out movement, O-2 also moves toward the specific Au atom horizontally. Besides, the adsorption energy (E-ad) of O-2 is dramatically changed with electric field. A negative electric field strengthens the interaction between O-2 and Au-doped graphene substrate, resulting in an enhanced E-ad; the corresponding O-O distance (d(O-O)) is also elongated, while E-ad is decreased and d(O-O) is shortened under a positive electric field. Because d(O-O) of the adsorbed O-2 correlates with its catalytic activation, the findings can provide a new avenue to tune the O-2 adsorption process onto Au-doped graphene substrate and may be useful in the future applications of graphene-based nanocatalyst.