Tailoring Metal Nanoclusters for Enhanced Electrocatalytic Reduction of CO 2 to CO

ABSTRACT The electrochemical reduction of CO 2 , as a renewable energy‐driven electrochemical system, has emerged as an environmentally benign approach for producing valuable chemicals and fuels under mild reaction conditions. Recent advances in the precise synthesis of metal nanoclusters, coupled with state‐of‐the‐art characterization techniques, have enabled atomic‐level investigation of structure–activity relationships in nanocatalysts. Due to their well‐defined atomic architectures, the active metal sites within these nanocatalysts can be accurately identified, facilitating systematic studies on how compositions (structures) modulate catalytic performance. This review begins by summarizing recent advances in the controlled synthesis of atomically precise metal nanoclusters, followed by an overview of progress in the electrochemical reduction of CO 2 to CO using nanoclusters as catalysts. Subsequently, we systematically investigate the effects of metal kernel characteristics and staple properties on catalytic activity, selectivity, and stability. Furthermore, current challenges are outlined, and prospective research directions are proposed in this rapidly evolving field. It is anticipated that this review will inspire further innovation in the synthesis of atomically precise nanocluster catalysts, promote a deeper mechanistic understanding of metal nanocluster‐mediated electrochemical CO 2 reduction, and push forward the related industrial applications.