Mixed-Valence Intermetallic Compounds for Urea Electrosynthesis
Gang Lin, Chaoqun Ma, Shuaishuai Xu, Huaifang Zhang, Xiao Ma, Fukai Feng, Yonghui Ren, Yanru Zhang, Wei Lin, Wenbin Cao, Xiangmin Meng, Lijie Zhu, Jing Xia, Qipeng Lu
Abstract
Efficient urea electrosynthesis relies on precisely controlling the kinetics of two parallel reduction reactions, i.e., carbon dioxide (CO 2 ) reduction and nitrate (NO 3 – ) reduction. However, a major challenge lies in constructing stable and different active sites at the atomic scale, which are essential for synchronizing the reaction kinetics of these two reactions and facilitating C–N coupling. Herein, we introduce a mixed-valence intermetallic compound (Mv-IMC) Cu 2 Sb, featuring Cu + –Cu 2+ dual-sites as modular building blocks to regulate and synchronize CO 2 and NO 3 – reduction kinetics. Mechanistic studies reveal that the constructed dual-sites stabilize *CO and *NO intermediates, lower the energy barrier of C–N coupling, and significantly enhance the urea synthesis efficiency. The Cu 2 Sb catalyst achieves a urea yield of 22.9 mmol h –1 g cat –1 with a Faradaic efficiency of 64.9% at −0.4 V, maintaining stability over 200 h, surpassing most previously reported catalysts. This work pioneers the precise construction of multivalent active sites in Mv-IMCs, establishing a paradigm for designing high-performance electrocatalysts tailored to value-added organic synthesis.