Coactivation of Multiphase Reactants for the Electrosynthesis of Urea
Zheng Lv, Shuanglong Zhou, Liang Zhao, Ziyi Liu, Jiaxin Liu, Wenxia Xu, Lei Wang, Jianping Lai
Abstract
Abstract N 2 and CO 2 fixation is an environmentally friendly waste‐to‐energy technology that can replace tedious and demanding industrial urea productive processes. Here, V N ‐Cu 3 N‐300 catalysts with tip and vacancy structures are designed for the coactivation of multiphase reactants in the urea electrosynthesis process. Under environmental conditions, the urea yield is 81 µg h −1 cm −2 , this is the first report of high area active electrocatalyst, and the corresponding Faraday efficiency is able to reach 28.7%. The full‐cell electrolysis exhibits good stability, providing a current density of 0.7 mA cm −2 at 2.1 V. The electrolyte after continuous electrolysis for 48 h is subjected to being evaporated and recrystallized, and it is determined by 1 H NMR that the purity of urea can reach 100%. Comprehensive analysis shows that the local electric field formed by the tip effect can effectively promote the adsorption and activation of CO 2 . The presence of surface nitrogen vacancies promotes the formation of *NN* intermediates, ensuring CN coupling, and also optimizing the dissociation process of water, providing a proton supply for the synthesis of urea. Thus, the rate‐determining step is altered and the formation of urea is ensured.