Multi‐Element Alloying and High‐Entropy‐Driven Catalytic Site Engineering: CuNiCoFeMn@KB High‐Entropy Alloy Achieves High Efficiency for Electroreduction of CO 2 to C 2
Bihua Hu, Weiming Shen, Ronghuan Liu, Xi Liu, Zhen Chen, Xiaoyu Zhang, Jiaxiang Guo, Kai Zong, Lin Yang, Xin Wang, Zhongwei ChenABSTRACT
Electrochemical carbon dioxide reduction reactions (CO 2 RR) offer a promising technological pathway for addressing greenhouse gas emissions, yet their complex reaction pathways and challenges in controlling product selectivity remain significant hurdles. In this study, a CuNiCoFeMn@KB high‐entropy alloy (HEA) catalyst was successfully synthesized via a one‐pot solvothermal reduction strategy. Structural and theoretical analyses suggest that the multi‐element alloying and high‐entropy‐like configuration alter the local surface composition and synergistically modulate the electronic structure, inducing an upshift of the d‐band center, which significantly enhances the adsorption of key reaction intermediates. Electrochemical evaluations demonstrated that the catalyst achieves a Faradaic efficiency of 57.3% for ethanol at −0.75 V versus RHE, with a current density of 32.83 mA cm −2 at −0.95 V, while maintaining robust long‐term stability exceeding 120 h. The regulatory mechanism of configurational entropy on CO 2 RR pathways was systematically investigated through a combination of density functional theory (DFT) calculations and experimental validation. Theoretical results indicate that *OCCO serves as the pivotal intermediate in the ethanol formation pathway. An increase in ΔS conf improves the thermodynamic preference for *OCCO dimerization, conferring a thermodynamic advantage for C─C coupling. This provides a potential “entropy regulation‐adsorption energy‐reaction pathway” correlation model. This work offers valuable theoretical insights and a promising material platform for the rational design of highly efficient catalysts for CO 2 RR.