Nickel and cobalt bimetallic hydroxide catalysts for urea electro-oxidation

Nickel-Cobalt bimetallic hydroxide electrocatalysts, synthesized through a one-step electrodeposition method, were evaluated for the oxidation of urea in alkaline conditions with the intention of reducing the oxidation overpotential for this reaction. The Nickel-Cobalt bimetallic hydroxide catalysts were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS). Raman spectroscopy, cyclic voltammetry (CV), and polarization techniques. A significant reduction in the overpotential (150 mV) of the reaction was observed with the Nickel-Cobalt bimetallic hydroxide electrode (ca. 43% Co content) when compared to a nickel hydroxide electrode. The decrease of the urea oxidation potential on the Nickel-Cobalt bimetallic hydroxide electrodes reveals great potential for future applications of urea electro-oxidation, including wastewater remediation, hydrogen production, sensors, and fuel cells. (C) 2011 Elsevier Ltd. All rights reserved.