Controlling the Morphology of CuO to Construct rich Cu ⁰ /Cu ⁺ Interfaces for CO ₂ Electroreduction to Multi‐Carbon Products

ABSTRACT It remains a significant challenge to electrocatalytically convert CO 2 into multi‐carbon (C 2+ ) products with both high selectivity and industrial‐grade current density. Herein, we report a pH‐directed strategy for growing CuO catalysts with precisely controlled morphologies. Among them, nanorod‐like CuO (R‐CuO) achieves an exceptional performance with a Faradaic Efficiency of 84.0% at 500 mA·cm −2 toward C 2 products. X‐ray photoelectron spectroscopy reveals that during electrochemical CO 2 reduction reaction (CO 2 RR), R‐CuO preserves the richest surface Cu + species (73.8%), thereby furnishing abundant Cu 0 /Cu + interfaces stemming from the unique “fragmentation‐agglomeration” reconstruction process. XAS results disclose a low coordination number (CN = 8.71) for the Cu─Cu scattering path and a high CN (0.72) for the Cu─O path in post‐reaction R‐CuO, underscoring its defective structure and Cu + retention. In situ characterizations further reveal that the robust Cu 0 /Cu⁺ interfaces markedly enhance the adsorption of OH − and * CO intermediate, accelerating the rate‐determining C─C coupling between * CO and * COH intermediates and driving selective C 2 formation. Therefore, we have established a relationship between the morphology of CuO and the pivotal Cu 0 /Cu + interfaces, providing a rational strategy for dynamically tailoring interface evolution toward selective C 2 production from CO 2 RR.