Strain Regulation Enhances the ^* CO Coverage on Cu ₂ O Surface for CO ₂ Electroreduction to Ethylene Under Industrial‐Level Current Density

ABSTRACT Electrochemical CO ₂ reduction reaction (CO ₂ RR) to ethylene (C ₂ H ₄ ) is still a significant challenge under industrial current density. In this study, Cu ₂ O with various lattice strain is prepared via an in situ reconstruction strategy. Notably, Cu ₂ O with 17.6% lattice strain rate (LS _17.6% Cu ₂ O) could achieve a Faradaic efficiency of 76.97% during CO ₂ RR to C ₂ H ₄ under the industrial current density of 800 mA cm ⁻² . Meanwhile, the energy efficiency of the cathode cell and full cell get 43.67% and 48.69%, respectively, which are the best values among Cu ₂ O catalysts. In situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy indicates that the LS _17.6% Cu ₂ O catalyst with moderate lattice strain possesses the highest surface coverage of ^* CO during the CO ₂ RR. Further density functional theory calculations reveal the moderate lattice strain shifts the d ‐band center of LS _17.6% Cu ₂ O from −2.28 to −2.06 eV, thereby enhancing the adsorption energy of ^* CO and reducing the energy barrier for the dimerization of ^* CO to form the ^* COCO intermediate. This work develops a precise strain regulation strategy to enhance the activity of CO ₂ electroreduction to ethylene under the industrial conditions.