Electrochemical decomposition of urea with Ni-based catalysts

Nickel based catalysts (Ni, Ni-Zn, and Ni-Zn-Co) synthesized through electrodeposition and alkaline leaching processes were used as electrocatalysts for the electrochemical decomposition of urea to benign nitrogen and fuel cell grade hydrogen. The performances of the Ni-based catalysts for the urea decomposition were investigated through cyclic voltammetry (CV) and polarization techniques. The results of the CVs show that the Ni-Zn catalysts and the Ni-Zn-Co catalysts decreased the onset potential of urea oxidation by 40 mV and 80 my, respectively when compared to Ni catalysts. The highest efficiency for the oxidation of urea was observed with the Ni-Zn-Co catalysts. The Ni-Zn and Ni-Zn-Co catalysts are promising materials for large-scale urea removal/decomposition from urea-rich wastewater, as well as for hydrogen production. (C) 2012 Elsevier B.V. All rights reserved.