Potential cycling effects on activities of nickel-mediated benzyl alcohol and glycine electrooxidation in alkaline solutions

Abstract

Nickel electrodes under continuous potential cycling were applied for the electrooxidation of benzyl alcohol and glycine in KOH solutions, and their activities were measured and compared by cyclic voltammetry. It is shown that intrinsic activities of both reactions decrease with the increasing catalyst loadings, and a more significant decreasing trend was observed in glycine electrooxidation when compared to benzyl alcohol electrooxidation. These phenomena may be explained by an increasing of mass loading induced a decrease of the catalyst surface conductivity, structure changes of Ni(OH)2 from α-phase to β-phase, and the intercalation of glycine molecules into nickel hydroxide interlayers.