Abstract：
In recent years, single-atom catalysts (SACs) have received increasing attention in the field of electrochemical CO2 RR with their efficient atom utilization efficiency and excellent catalytic performance. However, their low metal loading and the presence of linear relationships for single active sites with simple structures possibly restrict their activity and practical applications. Active site tailoring at the atomic level is a visionary approach to break the existing limitations of SACs. This paper first briefly introduces the synthesis strategies of SACs and DACs. Then, combining previous experimental and theoretical studies, this paper introduces four optimization strategies, namely spin-state tuning engineering, axial functionalization engineering, ligand engineering, and substrate tuning engineering, for improving the catalytic performance of SACs in the electrochemical CO2 RR process by combining previous experimental and theoretical studies. Then it is introduced that DACs exhibit significant advantages over SACs in increasing metal atom loading, promoting the adsorption and activation of CO2 molecules, modulating intermediate adsorption, and promoting C-C coupling. At the end of this paper, we briefly and succinctly summarize the main challenges and application prospects of SACs and DACs in the field of electrochemical CO2 RR at present.
摘要：
近年来,单原子催化剂(SAC)以其高效的原子利用率和优异的催化性能在电化学CO2RR领域受到越来越多的关注。然而,它们的低金属负载和具有简单结构的单个活性位点的线性关系的存在可能限制它们的活性和实际应用。在原子水平上进行主动位点定制是打破SAC现有限制的一种有远见的方法。本文首先简要介绍了SAC和DAC的合成策略。然后，结合以前的实验和理论研究，本文介绍了四种优化策略，即自旋状态调谐工程，轴向功能化工程，配体工程，和衬底调谐工程，通过结合先前的实验和理论研究来提高SAC在电化学CO2RR过程中的催化性能。然后介绍了DAC在增加金属原子负载方面比SAC表现出明显的优势，促进CO2分子的吸附和活化，调节中间吸附，促进C-C偶联。在本文的最后,简要总结了目前SACs和DACs在电化学CO2RR领域面临的主要挑战和应用前景。
