Enhanced Active Hydrogen Absorption and Stabilized Cu(I) Species Over Cu‐O‐Ce Bridges Boosting Electrocatalytic CO ₂ Reduction to Ethylene

Rational design of water activation center to promote active hydrogen (*H) generation and stabilize Cu(I) species are significant for the formation of multicarbon (C₂₊) products over Cu-based catalysts in electrocatalytic CO₂ reduction reaction (CO₂RR). Herein, CeO₂ nanograins and CuO nanothorns were selectively deposited on the edges of Cu₂O cubes through the seed-mediated growth method. The as-synthesized Cu_xO-CeO₂ composites exhibit enhanced Faradaic efficiency and partial current density of C₂H₄ compared with Cu₂O cubes. In situ spectroscopies and theoretical calculations confirm that the Cu-O-Ce bridges in Cu_xO-CeO₂ composite can effectively enhance *H absorption and stabilize Cu(I) species, facilitating subsequent C-C coupling and further protonation into the key *COCHO intermediate of C₂H₄. This work provides new insights into modulating *H absorption and stabilizing Cu(I) species for boosting CO₂ to C₂₊ products.