Rational Design of Transition Metal-Based Electrocatalyst Materials for Efficient Urea Oxidation Toward Hydrogen Production and Wastewater Treatment

Abstract

Hydrogen is widely recognized as a promising energy carrier that can reduce reliance on fossil fuels and address global climate and environmental challenges. Electrochemical water splitting provides a sustainable pathway for hydrogen production, but its overall efficiency is limited by the sluggish oxygen evolution reaction (OER). Benefiting from its low thermodynamic potential, the electrocatalytic urea oxidation reaction (UOR) has emerged as an appealing alternative to replace OER, while simultaneously enabling the remediation of urea-rich wastewater. This dual functionality highlights the urgent demand for highly efficient and durable UOR electrocatalysts. In this review, we first introduce the fundamental reaction mechanism of UOR and systematically summarize recent advances in the rational design strategies for transition metal-based electrocatalysts, such as element doping, morphology engineering, phase engineering, defect engineering, alloying, and heterostructure construction. Finally, the remaining challenges and future perspectives are discussed, aiming to provide comprehensive insights that will guide the development of efficient and sustainable UOR-based technologies for hydrogen production and wastewater treatment.