Interface‐Engineered AgMOF/Cu ₂ O Pyramids for Enhanced C ₂ H ₄ Selectivity in Electrochemical CO ₂ Reduction

ABSTRACT Cu‐based catalysts are widely explored for electrochemical CO ₂ reduction (eCO ₂ RR), but their application is limited by high overpotentials, poor selectivity, and stability issues. To address these challenges, we report the design of AgMOF/Cu ₂ O pyramid heterostructure catalysts with (111) lattice fringes, engineered lattice distortions, and abundant oxygen vacancies that effectively anchor Cu𝛿⁺ domains. Structural features at the AgMOF/Cu ₂ O interface provide rapid electron transfer pathways, as confirmed by in situ ATR‐FTIR measurements and theoretical simulations, thereby enhancing catalytic efficiency without requiring sacrificial agents. Moreover, the asymmetric interfacial sites with distinct charge distributions promote C–C coupling by stabilizing the ^* COCO intermediate, which drives the selective conversion of CO ₂ into ethylene (C ₂ H ₄ ). Density Functional Theory (DFT) calculations further demonstrate that the heterostructure enhances CO ₂ adsorption and lowers the energy barriers for key intermediates, establishing a favorable thermodynamic landscape for multi‐step reduction. Consequently, the optimized AgMOF/Cu ₂ O catalyst achieves a remarkable Faradaic efficiency of 61% for C ₂ H ₄ production at −1.1 V vs. RHE. These findings highlight that the synergistic interface engineering and charge‐polarized metal sites in AgMOF/Cu ₂ O heterostructures provide a promising strategy for advancing efficient CO ₂ electrolysis toward valuable multi‐carbon products.