Electrocatalysts for Urea Synthesis from CO<sub>2</sub> and Nitrogenous Species: From CO<sub>2</sub> and N<sub>2</sub>/NOx Reduction to urea synthesis
Li Chun, Qiuji Zhu, Chaojie Song, Yimin Zeng, Ying Zheng
Abstract
Abstract The traditional industrial synthesis of urea relies on the energy−intensive and polluting process, namely the Haber−Bosch method for ammonia production, followed by the Bosch−Meiser process for urea synthesis. In contrast, electrocatalytic C−N coupling from carbon dioxide (CO 2 ) and nitrogenous species presents a promising alternative for direct urea synthesis under ambient conditions, bypassing the need for ammonia production. This review provides an overview of recent progress in the electrocatalytic coupling of CO 2 and nitrogen sources for urea synthesis. It focuses on the role of intermediate species and active site structures in promoting urea synthesis, drawing from insights into reactants’ adsorption behavior and interactions with catalysts tailored for CO 2 reduction, nitrogen reduction, and nitrate reduction. Advanced electrocatalyst design strategies for urea synthesis from CO 2 and nitrogenous species under ambient conditions are explored, providing insights for efficient catalyst design. Key challenges and prospective directions are presented in the conclusion. Mechanistic studies elucidating the C−N coupling reaction and future development directions are discussed. The review aims to inspire further research and development in electrocatalysts for electrochemical urea synthesis.