Controllable synthesis of a mesoporous NiO/Ni nanorod as an excellent catalyst for urea electro-oxidation

Abstract

Mesoporous rod-like structured composites of NiO/Ni have been successfully prepared via a low temperature heat treatment of the precursor NiC₂O₄·2H₂O in N₂. The composites of NiO/Ni have the advantage of optimized electroactive sites, which can promote efficient mass transport through the mesoporous structure. Moreover, the evenly dispersed nanoparticles of nickel improve the electrical conductivity of the composites. Besides, the collaborative effects of both NiO and Ni further improve the kinetics of the urea electro-oxidation process. As expected, the composites exhibit a low overpotential of 120 mV at 10 mA cm⁻² (vs. RHE), good kinetics and outstanding catalytic stability for urea oxidation. All the results show that the mesoporous NiO/Ni obtained from nickel oxalate can provide valuable research data for improving the performance of direct urea fuel cells.