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.