A Light‐Switchable Polyoxometalate “Electron Pump” in a One‐Dimensional Copper Coordination Polymer: Near‐Unity Selective CO 2 Photoreduction to Methane
Chang Liu, Wei Geng, Yuxuan Tan, Jiayang Shi, Faheem Abbas, Yanan Fan, Sha Zhang, Haili Song, Yu Zhang, Duidui Zhang, Chen Chen, Cheng‐Xia Chen, Cheng‐Yong Su, Yongge WeiABSTRACT
Photocatalytic CO 2 reduction to methane (CH 4 ) is highly desirable but severely hindered by sluggish multiple proton‐coupled electron transfer (MPCET) kinetics and poor product selectivity. In this study, we report a novel one‐dimensional (1D) copper coordination polymer, termed Cu‐PMo 12 , featuring single‐site Cu centers periodically bridged by Keggin‐type {PMo 12 } clusters. Comprehensive experimental and theoretical studies reveal a synergistic mechanism governed by static electronic modulation and dynamic photoactivation. In the ground state, {PMo 12 } acts as an electron acceptor, withdrawing electrons from Cu sites to upshift the Cu d ‐band center, thereby strengthening the binding affinity toward intermediates. Under visible‐light irradiation, {PMo 12 } functions as a photosensitizer and a light‐switchable “electron pump”, directionally injecting photogenerated electrons to Cu sites to dynamically maintain highly active Cu(I) species for the subsequent MPCET process. Consequently, Cu‐PMo 12 achieves an exceptional CH 4 evolution rate of 70.5 µmol g Cu − 1 h − 1 with near‐unity selectivity (∼100%) and excellent durability. This work highlights precise microenvironment engineering via polyoxometalate‐metal integration and provides a paradigm for designing light‐driven “electron pump” systems for challenging multi‐electron catalytic transformations.