Dynamic nano-pulling effect of the boron-functionalized graphene monovacancy for molecule dissociation.

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 H2 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 H2 dissociation compared to that of 4.58 eV for free H2 molecules. This method may open up new avenues for the development of safe hydrogen storage and biomimic photosynthesizers. [ABSTRACT FROM AUTHOR]