Towards Sustainable Energy-Saving Hydrogen Production: Recent Advances in Tungsten-Based Urea Oxidation Electrocatalysts.

The urea oxidation reaction (UOR), as a multi-electron coupling reaction, provides an efficient route for treating urea-containing wastewater and a sustainable strategy for energy-saving H2 production. Nickel-based catalysts attract attention due to their low cost and favorable activity, but single-metal catalysts still suffer from limited activity and stability. To overcome these limitations, researchers enhance performance through doping, structural regulation, and composite strategies. Tungsten (W), with high electronegativity, multivalence, excellent conductivity, and environmental friendliness, is widely incorporated into nickel-based catalysts to modulate electronic structure, improve adsorption and conversion of intermediates, and enhance stability. This review summarizes recent progress in W-based UOR catalysts, focusing on reaction mechanisms, structural regulation strategies, and performance improvement approaches. Current challenges include active site identification, catalyst stability, reaction selectivity, and the lack of standardized evaluation protocols. Future research directions involve elucidating catalytic mechanisms, optimizing material design, establishing unified evaluation standards, and developing high-performance W-based composites, aiming to advance UOR applications in energy conversion, wastewater treatment, and sensing.