Trace Cu‐Induced Low C─N Coupling Barrier on Amorphous Co Metallene Boride for Boosting Electrochemical Urea Production

Abstract The electrochemical C─N coupling of carbon dioxide (CO 2 ) and nitrate(NO 3 ‐ ) is an alternative strategy to the traditional high−energy industrial pathway for urea synthesis, which urgently requires the design of efficient catalysts to achieve high yield and Faraday efficiency (FE). Here, amorphous low‐content copper‐doped cobalt metallene boride ( a ‐Cu 0.1 CoB x metallene) is designed for urea synthesis via electrochemical C─N coupling. The a ‐Cu 0.1 CoB x metallene can drive electrocatalytic C─N coupling of CO 2 and NO 3 − for urea synthesis in CO 2 ‐saturated 0.1 m KNO 3 electrolyte, with 27.7% of FE and 312 µg h −1 mg −1 cat. of yield at −0.5 V, as well as superior cycling stability. The in situ Fourier transform infrared and theoretical calculations reveal that electronic effect between Cu, Co, and B causes Cu and Co as dual active sites to promote the adsorption of reactants. Furthermore, the introduced trace Cu reduces the reaction energy barrier of the C─N coupling to facilitate urea synthesis. This work provides a promising route for the optimization of Co‐based metallene for the electrosynthesis of urea through C─N coupling.