▎ 摘　　要

Atoms on charged graphitic carbon surface are relevant to various electrochemical problems, understanding the adsorption and diffusion of adatoms under charging conditions is essential towards using graphene-like materials in electrochemistry. Using density functional calculations, we show that electron or hole doped graphene can strongly change the mobility of H and O adsorbed atoms. Interestingly, charge doping affects the diffusion of H and O in opposite ways, namely, electron doping increases/reduces, while hole doping reduces/increases the diffusion barrier of H/O respectively. Specifically, on neutral graphene the diffusion barriers of H and O are 1.01 and 0.74eV, which are, upon a hole doping level of +5.9 x 10(13) cm(-2), 0.77 and 0.90eV, and upon an electron doping level of -5.9 x 10(13) cm(-2), 1.36 and 0.38eV. Thus, within the harmonic transition state theory, at room temperature, the diffusion rate of O can be decreased or increased by 470 or 1 x 10(6) times, while that of H can be increased or decreased by 1 x 10(4) or 7 x 10(5) times, respectively for the above hole or electron doping density. The difference between H and O atomic transport at charged graphene is interpreted in terms of the difference in geometric and bonding changes upon charge doping.