Summary and application of Ni-based catalysts for electrocatalytic urea oxidation

At present, energy shortage and environmental pollution are becoming more and more serious. If environmental governance and energy supply can be combined, it will be more consistent with the long-term concept of sustainable development. Urea electrooxidation may achieve the degradation of pollutants and the conversion of energy supply, urea oxidation occurs at the anode and hydrogen evolution occurs at the cathode. However, the electrochemical oxidation process of urea requires the transfer of six electrons, and the reaction rate is slow. The electrocatalyst is a key factor in improving the reaction kinetics. In this context, catalysts used in urea electrocatalytic oxidation in recent years are reviewed in this paper. The application of the electrocatalyst in electrolytic hydrogen production, urea wastewater treatment, urea fuel cells and urea sensors are described in detail. In addition, the future research directions, research emphases and areas needing improvement of these catalysts are discussed.