Efficient Electrochemical Co‐Reduction of Carbon Dioxide and Nitrate to Urea with High Faradaic Efficiency on Cobalt‐Based Dual‐Sites

Abstract

AbstractRenewable electricity‐powered nitrate/carbon dioxide co‐reduction reaction toward urea production paves an attractive alternative to industrial urea processes and offers a clean on‐site approach to closing the global nitrogen cycle. However, its large‐scale implantation is severely impeded by challenging C–N coupling and requires electrocatalysts with high activity/selectivity. Here, cobalt‐nanoparticles anchored on carbon nanosheet (Co NPs@C) are proposed as a catalyst electrode to boost yield and Faradaic efficiency (FE) toward urea electrosynthesis with enhanced C–N coupling. Such Co NPs@C renders superb urea‐producing activity with a high FE reaching 54.3% and a urea yield of 2217.5 µg h−1 mgcat.−1, much superior to the Co NPs and C nanosheet counterparts, and meanwhile shows strong stability. The Co NPs@C affords rich catalytically active sites, fast reactant diffusion, and sufficient catalytic surfaces‐electrolyte contacts with favored charge and ion transfer efficiencies. The theoretical calculations reveal that the high‐rate formation of *CO and *NH2 intermediates is crucial for facilitating urea synthesis.