Bimetallic CuCe nanosponges for boosting CO2 electroreduction to generate C2+ products via Ce(4f)-O(2p)-Cu(3d) gradient orbital coupling

Electrochemical CO 2 reduction (ECO 2 RR) is a sustainable approach to produce high-value C 2+ products, yet conventional Cu catalysts show poor C 2+ selectivity due to unfavorable *CO adsorption and unstable Cu + . Herein, Ce-doped Cu nanosponges with regulated Ce content are developed for efficient ECO 2 RR. Experimental results demonstrate that optimal Ce doping constructs Ce-O-Cu bridge sites, triggering Ce(4f)-O(2p)-Cu(3d) orbital coupling and electron redistribution. DFT results prove the lowered Cu d-band center weakens *CO binding and reduces C-C coupling energy barrier, and Ce also accelerates electron transfer. The optimized catalyst delivers a C 2+ Faradaic efficiency of 67.9% (46.3% for C 2 H 4 ) at −1.3 V vs. RHE and maintains stability over 12 h. This work elucidates the modulation mechanism of Ce and offers a strategy to boost C 2+ selectivity.