One-step synthesis of boron and nitrogen-dual-self-doped graphene sheets as non-metal catalysts for oxygen reduction reaction

Abstract

A facile method has been used to synthesize boron and nitrogen-dual-self-doped graphene sheets (BNGs). The procedures include a borane-tert-butylamine complex as the precursor to impregnate with a certain amount of cobalt ions, then thermolysis in a tube furnace. The synthesized boron and nitrogen-dual-self-doped graphene sheets are systematically characterized by XRD, Raman spectra, XPS, SEM, EDS, TEM and EELS. Analysis results show that nitrogen and boron atoms are successfully self-doped into the graphene sheets. The BNG-1000 indicates the nitrogen and boron doping levels of 7.72 at.% and 7.18 at.%, respectively. The BNGs show a remarkable activity and high stability for the oxygen reduction reaction (ORR). An onset potential of 0.95 V which is close to that of Pt/C and a well-defined limiting current plateau for the ORR is observed in alkaline media. It has been evidenced that the catalyst is very stable and without degradation after 5000 cycles.