  Nitrogen-doped graphene was recently synthesized and was reported to be a
catalyst for hydrogen dissociative adsorption under a perpendicular applied
electric field (F). In this work, the diffusion of H atoms on N-doped graphene,
in the presence and absence of an applied perpendicular electric field, is
studied using density functional theory. We demonstrate that the applied field
can significantly facilitate the binding of hydrogen molecules on N-doped
graphene through dissociative adsorption and diffusion on the surface. By
removing the applied field the absorbed H atoms can be released efficiently.
Our theoretical calculation indicates that N-doped graphene is a promising
hydrogen storage material with reversible hydrogen adsorption/desorption where
the applied electric field can act as a switch for the uptake/release
processes.
