Nickle-cobalt composite catalyst-modified activated carbon anode for direct glucose alkaline fuel cell

Abstract

Glucose is the most abundant monosaccharide in nature and has great potential as high-density hydrogen carrier for fuel cells. However, the practical application of direct glucose alkaline fuel cell (DGAFC) is hampered by lack of cost-effective anode catalyst. In this study, nickel-cobalt composite catalysts were prepared by NaBH4 reduction method and electrochemical, morphological and chemical properties of catalysts were characterized by LSV, EIS, SEM, TEM, XRD and XPS techniques. The nickel-cobalt composite catalyst and modified activated carbon anode was evaluated in one-chamber DGAFC. Our results demonstrated that the DGAFC performance was greatly improved with the addition of Ni-Co composite catalyst in the anode. Fuel cell achieved the peak power density of 23.97 W m−2 under the condition of 1 M glucose, 3 M KOH and ambient temperature. The enhancement of the anode performance could be attributed to the synergic effect of two reversible redox systems, Ni(II)/Ni(III) and Co(II)/Co(III), which improved interfacial charge-transfer kinetics. Our study may facilitate the development of cost-effective renewable energy devices.