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

Electrocatalytic C-N bond coupling to convert CO 2  and N 2  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 driving C-N coupling reaction is energetically challenging. Herein, a novel Mott-Schottky Bi-BiVO 4  heterostructures are designed and realize the remarkable urea yield rate of 5.91 mmol h -1  g -1  and Faradaic efficiency of 12.55% at -0.4 V vs. RHE. Comprehensive analysis confirms the emerged space-charge region in heterostructural interface not only facilitates the targeted adsorption and activation of CO 2  and N 2  molecules on generated the local nucleophilic and electrophilic region but also effectively suppresses CO poisoning and the formation of endothermic *NNH intermediate, which thus guarantees the exothermic coupling of *N=N* intermediates and generated CO via desired C-N coupling reaction to form urea precursor *NCON* intermediate. This work provides an encouraging inspiration to promote urea electrosynthesis by electrochemical C-N coupling reaction under ambient conditions.