Selectively Electrochemical Reduction of CO₂ Based on Metal Clusters Catalysts

The electrochemical CO₂ reduction reaction (eCO₂RR) has emerged as a pivotal technology for addressing global climate challenges by converting CO₂ into value-added chemicals, thereby contributing to carbon neutrality efforts. Metal nanoclusters, characterized by their atomically precise structures and unique electronic properties, have gained significant attention as highly tunable catalysts for eCO₂RR due to their exceptional activity and selectivity. This review systematically summarizes recent advancements in metal nanoclusters for CO₂ conversion. First, the fundamental reaction mechanisms and pathways governing the formation of key products such as CO, formic acid, and hydrocarbons are elucidated. Next, the catalysts involved in eCO₂RR, including noble metal (e.g., Au, Ag) and non-noble metal (e.g., Cu, Ni) clusters are summarized, and the latest technical strategies for enhancing CO₂ reduction efficiency, such as alloying, ligand engineering, defect engineering, and heteroatom doping are presented. Finally, the challenges of metal nanoclusters in eCO₂RR are discussed and future research directions and development prospects are outlined. This review puts forward the cutting-edge design strategy of atomic-level precise metal nanocluster catalysts in eCO₂RR, which not only deepens the understanding of the basic science of electrocatalysis but also provides a feasible technical roadmap for realizing a sustainable CO₂ circular economy.