Rational Design and Validation of Cu 2 O/Cu Heterogeneous Interface Catalyst for CO 2 Electroreduction to C 2+ Products

Abstract Rapid construction of highly active non‐precious metal catalysts for electrochemical CO 2 reduction reaction (CO 2 RR) to C 2+ products is still challenging. Under the guidance of theoretical calculation, the Cu 2 O(200)/Cu(111) is screened heterogeneous catalyst which is favorable for arduous CO 2 activation and unstable * CO adsorption during the electrochemical CO 2 RR. Then, a novel Cu 2 O(200)/Cu(111) heterogeneous interface is fabricated by an ambient precipitation coupled chemical reduction strategy. Notably, the obtained Cu 2 O/Cu exhibits excellent activity for CO 2 RR, which FE C2+ is 82.98% under the industrial current density of 450 mA cm −2 in membrane electrode assembly cell. In situ X‐ray photoelectron spectroscopy combined with spherical aberration correction electron microscope reveals Cu 2 O/Cu interface exhibits the excellent structural durability. Furthermore, in situ Raman and in situ attenuated total reflection‐surface‐enhanced IR absorption spectroscopy directly capture * COOH, * CHO, and * COCHO intermediates, disclosing the formation of the C 2+ products involves in the * COCHO pathway. Mechanism studies demonstrate the presence of charge aggregation at Cu 2 O/Cu interface directly reduces the energy barrier for C─C coupling (rate‐determining step) to 0.76 eV. This work developed a highly active heterogeneous interface for CO 2 RR, which provides a novel insight for the fabrication of Cu‐based catalysts.