Reconstructed Copper Compound by Cerium Leaching for Enhanced Electrochemical CO₂-to-Ethylene Conversion

Rationally modulating the reconstructed structure of electrocatalyst is an effective avenue toward selective electrochemical CO₂ reduction (e-CO₂RR). Herein, it is reported that a Ce-incorporated Cu oxide (CeCuO_x) can have prominent performance for the selective production of C₂H₄ 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 Cu⁰/(Cu⁺+Cu²⁺) 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 C₂H₄ selectivity and efficiency. Our work provides new insights into the relationship between the reconstructed structure and mechanism for boosting CO₂ to multi-carbon products.