Support engineering drives the CO₂ electro-reduction performance of single-atom catalysts: structure-activity relationships and strategic regulation

Single-atom catalysts (SACs) have recently attracted considerable attention in the field of electrocatalytic CO₂ reduction (ECR) due to their nearly 100 % atomic utilization efficiency and highly tunable electronic structure properties. Crucially, the support material in SACs systems transcends conventional physical support roles, instead dictating catalytic performance—activity, selectivity, and stability—via atomic-scale anchoring site engineering, electronic control mechanism, and coordination environment optimization. Based on this understanding, this paper systematically reviews the latest research progress of SACs loaded on different support materials in the field of ECR. Firstly, the main preparation and characterization methods of SACs are briefly outlined. Secondly, the support engineering strategies for SACs are discussed in detail, with an in-depth analysis of how different support designs precisely regulate the coordination environment and electronic structure of SACs through structure-activity relationships. Finally, based on the current state of research, the development prospects of SACs in the ECR field are summarized and discussed. This review provides important references for understanding the structure-activity relationship regulation mechanisms of SACs and their applications in directed ECR.