  Hydrazine stands out as the most generally used chemical-reducing agent for
reducing graphene oxide. Despite numerous experimental and theoretical
investigations into the reduction reaction, the reduction mechanism remains
unclear. In this study, we propose that, in aqueous hydrazine solutions, both
hydrazine and hydroxide ions could initiate the reduction of graphene oxide. We
introduce a chemical reaction pathway involving C-H cleavage and a
dehydroxylation process for the reduction of graphene oxide. By utilizing
density functional theory calculations, the reduction reactions mediated by
hydrazine and hydroxide ions are separately investigated. The reaction routes
on the basal plane and edge regions of graphene oxide are discussed
independently. The density functional theory calculations demonstrate that the
proposed mechanism is both thermodynamically and dynamically feasible. This
work might contribute to an atomic-level comprehension of a longstanding
challenge in the field of graphene oxide.
