▎ 摘　　要

Based on density-functional theory, we find that B-doped graphene significantly enhances the Be adsorption energy and prevent Be atoms from clustering. The complex of Be adsorbed on B-doped graphene can serve as a high-capacity hydrogen storage medium: the hydrogen storage capacity (HSC) can reach up to 15.1 wt% with average adsorption energy -0.298 eV/H-2 for double-sided adsorption. It has exceeded the target specified by US Department of Energy with HSC of 9 wt% and a binding energy of -0.2 to -0.6 eV/H-2 at near-ambient conditions. By analyzing the projected electronic density of states of the adsorbed system, we show that the high HSC is due to the change of electron distribution of H-2 molecules and a graphene system decorated with B and Be atoms. (C) 2011 Elsevier Ltd. All rights reserved.