Rational structural engineering strategies for electrochemical CO₂ reduction on copper

The electrochemical reduction of carbon dioxide (CO₂RR) offers a promising pathway for converting CO₂ into value-added chemicals and fuels, thereby mitigating greenhouse gas emissions and enabling carbon resource utilization. Copper-based catalysts have attracted considerable attention due to their unique capability to produce a wide range of C₁ and C₂ products. Nevertheless, challenges such as low selectivity, poor stability, and inefficient reaction kinetics impede their practical application. This review comprehensively summarizes recent advances in the structural engineering of Cu-based electrocatalysts for enhanced CO₂RR performance. Key strategies-including interface engineering, phase engineering, doping engineering, and defect engineering-are discussed in detail, emphasizing their roles in modulating electronic structures, surface morphologies, and reaction pathways. In particular, we provide insights into the reaction mechanisms and intermediate stabilization facilitated by these structural modifications. Finally, current challenges and future directions for the rational design of high-performance Cu-based catalysts toward sustainable CO₂ conversion are outlined.