Unveiling Electrochemical Urea Synthesis by Co-Activation of CO₂ and N₂ with Mott–Schottky Heterostructure Catalysts

Electrocatalytic C−N bond coupling to convert CO₂ and N₂ molecules into urea under ambient conditions is a promising alternative to harsh industrial processes. However, the adsorption and activation of inert gas molecules and then the driving of the C–N coupling reaction is energetically challenging. Herein, novel Mott–Schottky Bi-BiVO₄ heterostructures are described that realize a remarkable urea yield rate of 5.91 mmol h⁻¹ g⁻¹ and a Faradaic efficiency of 12.55 % at −0.4 V vs. RHE. Comprehensive analysis confirms the emerging space–charge region in the heterostructure interface not only facilitates the targeted adsorption and activation of CO₂ and N₂ molecules on the generated local nucleophilic and electrophilic regions, but also effectively suppresses CO poisoning and the formation of endothermic *NNH intermediates. This guarantees the desired exothermic coupling of *N=N* intermediates and generated CO to form the urea precursor, *NCON*.