Physically mixed Ni₂Co/graphene catalyst for enhanced glucose oxidation in a glucose fuel cell

Glucose oxidation reaction is kinetically sluggish and demands a highly efficient catalyst. Herein, we report a direct glucose alkaline fuel cell (DGAFC) using physically mixed Ni2Co nanoparticles and reduced graphene oxide (Ni2Co-rGO) supported on nickel foam as an anode to promote glucose oxidation. The DGAFC with the Ni2Co-rGO anode delivered a remarkably enhanced peak power density of 40.44 W/m(2) at room temperature, which was 74.91% higher than the control (23.12 W/m(2)). Different techniques including XPS, SEM, linear sweep voltammetry, and electrochemical impedance spectroscopy were used to explore the physiochemical and electrochemical properties of the catalyst. Our results demonstrate that Ni2Co-rGO exhibits an excellent activity toward glucose oxidation in alkaline medium, leading to a drastic improvement in the anode performance. There should be a synergistic effect between rGO and NNi2Co. In the Ni2Co-rGO nanocomposite, rGO not only acts as a support for the Ni2Co nanoparticles and also promotes the electron transfer during the glucose oxidation process. This study can promote the development of bi-transition metal-based catalysts for DGAFCs.