A three-dimensional nickel-cobalt oxide nanomaterial as an enzyme-mimetic electrocatalyst for the glucose and lactic acid oxidation reaction

Here we demonstrate a highly porous three-dimensional nickel-cobalt oxide (NiCo2O4) nanomaterial as a potential glucose oxidase (GOx) enzyme-mimicking catalyst for the electrochemical oxidation of glucose and lactic acid in alkaline medium. The as-synthesized NiCo2O4 nanomaterial based anode exhibits an excellent catalytic activity towards glucose oxidation with a low oxidation potential of similar to 0.43 V (vs. Ag/AgCl), a high current density of similar to 26.2 mA cm(-2), a high mass activity of similar to 263.0 A g(-1) and a long term durability of over similar to 500 continuous cycles. The flower-like NiCo2O4 nanomaterial delivers an over similar to 1.4, similar to 1.9, and similar to 2.0 times higher catalytic current density with a less positive shift by similar to 70 mV, similar to 80 mV and similar to 40 mV, respectively, when compared to NiO, Co3O4, and commercial Pt/C. The enhanced catalytic activity of the as-developed Earth-abundant NiCo2O4 nanomaterial may be ascribed to its exclusive architecture with a less agglomerated structure, high electrochemically active surface area (ECASA), small pore size, mixed active sites of nickel and cobalt cations and favourable atmosphere for the enriched electron transfer process between analytes and electrodes. The present anode material is competent in performing direct electron transfer to the surface of the electrode and removes the requirement for enzymes and mediators.