Synthesis of Nitrogen-doped Graphene and Its Electrocatalytic Performance Toward Oxygen Reduction Reaction

A nitrogen-doped graphene with high electrocatalytic abilities toward oxygen reduction reaction(ORR)was prepared via physical mixture of graphene oxide and melamine and one-step pyrolysis in N2.According to the scanning electron microscopy(SEM)measurements,the nitrogen-doped graphene prepared from melamine has higher thickness and overlap.Xray photoelectron spectroscopy(XPS)shows that nitrogen is successfully doped in graphene with the formation of pyrrole-like N,pyridine-like and graphitice-like N,the content ratios of different nitrogen were calculated to be 14.5 %(at),24.5%(at)and 61.0%(at),respectively.According to cyclic voltammogram(CV)and rotating disk electrode(RDE)measurement,the as-prepared nitrogen-doped graphene exhibit higher electrocatalytie activity with an onset potential of-0.1Vin an alkaline electrolyte in comparison with commercial graphene and polypyrrole-doped grapheme(ppy-NG),and the overall electron transfer number in the catalyzed ORR was found to be 4.Due to high electrocatalytie activity for ORR and low costs,the nitrogendoped graphene prepared from melamine would be a potential candidate as an cathode electrocatalyst in alkaline fuel cell.