Phosphorus-Mediated Oxygen Vacancy Engineering in Cu<sub>2</sub>O for Highly Selective CO<sub>2</sub> Electroreduction to Multicarbon Products
Xiaoqing Mao, Zhongyuan Guo, Saiwu Yang, Yongjun Shen, Wei Li, Congcong Li, Congcong Li, Hongliang Jiang, Hao Li, Huihui Li, Chunzhong Li, Chunzhong Li
Abstract
Copper (Cu)-based electrocatalysts are acknowledged as pivotal catalysts for the electroreduction of CO 2 into multicarbon (C 2+ ) products; however, achieving high C 2+ selectivity at industrial-level current densities remains a significant challenge. Herein, we propose a “phosphorus (P)-doping mediation” strategy to introduce an oxygen vacancy into the Cu 2 O lattice, resulting in a C 2+ Faradaic efficiency of 87.0% at a partial current density of 347.8 mA·cm –2 . Mechanistic studies unveil that P dopants dynamically regulate the formation of high-density oxygen vacancies in Cu 2 O lattices through the formation and subsequent detachment of the P–O bond, predominantly in the form of phosphite within an aqueous electrolyte environment. In situ Raman spectroscopy coupled with density functional theory calculations further reveals that the OV-rich structure optimizes the surface coverage of active *CO intermediates. This microenvironment not only accelerates the energetically favorable C–C coupling pathway but also suppresses competitive protonation reactions, thereby breaking the intrinsic activity-selectivity trade-off. Our work provides atomic-level insights into defect dynamics manipulation for designing high-rate CO 2 conversion systems.