Cu-Rich High-Entropy Alloy Aerogels for Efficient Carbon Dioxide Reduction

High-entropy alloy aerogels (HEAAs) have emerged as promising catalysts that combine multimetallic synergy and surface unsaturated sites for renewable energy conversion, yet the development of efficient and low-cost HEAAs remains challenging. In this study, for the first time, Cu-rich CuBiInZnPd HEAAs were prepared as efficient electrocatalysts for the carbon dioxide reduction reaction (CO 2 RR). Compared with low-entropy counterparts such as CuPd metallic aerogels (MAs) and Cu MAs, the CuBiInZnPd HEAAs possess a higher Faradaic efficiency for formate of 94.7% at −1.0 V versus the reversible hydrogen electrode during the CO 2 RR. Moreover, CuBiInZnPd HEAAs demonstrate excellent operational stability, maintaining nearly constant current density over 20 h. Mechanism research indicates that the multimetallic synergy and surface unsaturated sites in CuBiInZnPd HEAAs influence the surface electronic structure of Cu and the adsorption of reaction intermediates, consistent with the observed CO 2 RR performance. This work provides a new approach for the functionalization of HEAAs and offers new ideas for the design of low-cost CO 2 RR electrocatalysts.