▎ 摘　　要

We investigate the molecule dissociation and separation roles of graphene membranes with different functionalized monovacancies using first-principles density functional theory calculations. We have found that the boron-functionalized graphene vacancy can effectively dissociate one H-2 molecular into two hydrogen atoms through a novel nano-pulling effect; at the same time it can separate the two hydrogen atoms on different sides of the graphene monolayer, with about 0.21 eV net adsorption energy. The boron-functionalized monovacancy acts like a pair of nanoscissors in this process. The binding energies of the two separated hydrogen atoms with the boron-functionalized monovacancy are 2.82 eV and 1.54 eV, respectively, in the two releasing steps. The boron-functionalized graphene monovacancy as a molecular dissociator can remarkably decrease the potential barrier of H-2 dissociation compared to that of 4.58 eV for free H-2 molecules. This method may open up new avenues for the development of safe hydrogen storage and biomimic photosynthesizers.