Construction of Low‐Coordination Cu−C2 Single‐Atoms Electrocatalyst Facilitating the Efficient Electrochemical CO2 Reduction to Methane

Abstract Constructing Cu single‐atoms (SAs) catalysts is considered as one of the most effective strategies to enhance the performance of electrochemical reduction of CO 2 (e‐CO 2 RR) towards CH 4 , however there are challenges with activity, selectivity, and a cumbersome fabrication process. Herein, by virtue of the meta‐position structure of alkynyl in 1,3,5‐triethynylbenzene and the interaction between Cu and −C≡C−, a Cu SAs electrocatalyst (Cu−SAs/HGDY), containing low‐coordination Cu−C 2 active sites, was synthesized through a simple and efficient one‐step method. Notably, this represents the first achievement of preparing Cu SAs catalysts with Cu−C 2 coordination structure, which exhibited high CO 2 ‐to‐CH 4 selectivity (72.1 %) with a high CH 4 partial current density of 230.7 mA cm −2 , and a turnover frequency as high as 2756 h −1 , dramatically outperforming currently reported catalysts. Comprehensive experiments and calculations verified the low‐coordination Cu−C 2 structure not only endowed the Cu SAs center more positive electricity but also promoted the formation of H•, which contributed to the outstanding e‐CO 2 RR to CH 4 electrocatalytic performance of Cu−SAs/HGDY. Our work provides a novel H⋅‐transferring mechanism for e‐CO 2 RR to CH 4 and offers a protocol for the preparation of two‐coordinated Cu SAs catalysts.