The enhanced electrocatalytic activity of graphene co-doped with chlorine and fluorine atoms

•Developed a one-step synthesis of graphene co-doped with different halogen atoms.•The obtained graphene exhibits great electrocatalytic activity in the oxygen reduction reaction.•The chlorine–fluorine co-doped graphene has great stability in methanol crossover effect.•Experiments indicate that there are possible synergetic interactions between halogen dopants.

Graphene co-doped with fluorine and chlorine heteroatoms was prepared through a one-step synthesis and was investigated as the oxygen reduction electrocatalysts. Voltammetric measurements show that fluorine and chlorine co-doped graphene has remarkable catalytic activity toward the electrochemical reduction of oxygen in alkaline solution. Besides having a high tolerance to methanol crossover effect, the co-doped graphene also showed a better stability than that of commercial Pt/C electrocatalysts and of the chlorine-doped graphene that was prepared by the same approach. The charge transfer resistance of the co-doped graphene was substantially lower than that of the chlorine-doped graphene, suggesting that there may exist a synergistic interaction between fluorine and chlorine dopants. The rapid synthetic method reported here provides an effective approach for future investigation of halogen (co-) doped graphene.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideGraphene co-doped with fluorine and chlorine was prepared through a one-step synthesis to greatly enhance its electrocatalytic activity and stability for oxygen reduction reaction.