Room-Temperature Transformation of Bulk Materials into Single Atoms for Advancing CO ₂ Electroreduction Efficiency

Metal single-atom catalysts (SACs) offer exceptional atomic efficiency and remarkable properties, making them highly valuable for energy and environmental applications. However, existing SAC preparation methods face challenges, such as the need for high temperatures or limitations in metal loading. In this study, we present a room-temperature synthesis strategy for stable SACs with high metal loadings (>10 wt %), achieved through electrochemical redox reactions within lithium-ion batteries. The reaction mechanism was thoroughly elucidated, revealing that bulk metallic compounds (denoted as M_<i>a</i>X_<i>b</i>, where M represents a metal and X is F, S, or O) disintegrate from the millimeter scale down to single atoms at room temperature. This process is driven by lithiation-delithiation-induced grain refinement and the dissolution of metals, which are subsequently captured by the substrate. The resulting single-atom catalyst (e.g., Cu SAC) demonstrates outstanding reactivity for electrocatalytic CO₂ reduction, showcasing excellent electrochemical stability and superior performance. This room-temperature redox method is versatile and compatible with a wide range of metals and supports, highlighting its potential for broad applications in sustainable catalytic technologies.