Synthesis of defect-impressive boron graphene as a remarkable electrocatalyst for methanol oxidation reaction

Abstract

Boron defect graphene (BdG) of a forked tree like structure is successfully fabricated using a vacuum-thermal annealing of boric acid at 900 oC under the argon gas stream. It's thoroughly characterized together with the reduced graphene oxide and graphene oxide arrangements by XRD, TEM, Raman, N 2 adsorption, XPS and electronic conductivity. BdG that exhibits high average surface area, high p-type conductivity and appreciable porosity delivers an exceptional methanol oxidation reactivity than RGO and GO and surprisingly exceeds that of the commercial Pt/C catalysts. The BdG electro-catalyst indicates higher current density comprised of 21.0 mA cm−2 than RGO (4 times) and Pt/C (2 times) electrodes in an alkaline medium. The reaction kinetics, charges transfer resistance, and stability are thoroughly determined. The obtained results revealed that the defect sites launched by boron insertion include the existence of B–O and B2CO beside the porosity are recognized as highly active sites for methanol oxidation. Based on the obtained results, a proposed mechanism has been designed. The CO tolerance of the BdG indicates lower onset potential and peak potential compared to the Pt/C electrode and rather reflects the role of the former defects on facilitating the methanol oxidation.