Reconstructed Copper Compound by Cerium Leaching for Enhanced Electrochemical CO 2 ‐to‐Ethylene Conversion

Abstract Rationally modulating the reconstructed structure of electrocatalyst is an effective avenue toward selective electrochemical CO 2 reduction (e‐CO 2 RR). Herein, it is reported that a Ce‐incorporated Cu oxide (CeCuO x ) can have prominent performance for the selective production of C 2 H 4 with a high Faraday efficiency (FE) of 55.39% at −0.93 V, and partial current density of −39.50 mA cm −2 at −1.03 V, higher than those of Cu oxide and Cu at the same potential. Systematical experimental investigations show that the CeCuO x reconstructs to oxygen‐contained Cu with optimized Cu 0 /(Cu + +Cu 2+ ) ratio and electronic structure through Ce leaching and in situ reduction. All of those benefit water molecule cleavage and OH − accumulation that could provide hydrogen feedstock and suppress competitive hydrogen evolution. Importantly, specific C 1–2 intermediates generation and activation are enhanced, achieving high C 2 H 4 selectivity and efficiency. Our work provides new insights into the relationship between the reconstructed structure and mechanism for boosting CO 2 to multi‐carbon products.