Atomically precise metal nanoclusters for energy conversion

Atomically precise metal nanoclusters (NCs) have emerged as a new frontier in electrocatalysis, enabling the study of electrocatalytic reactions on well‐defined stable surfaces and rational electrocatalyst design based on atomic‐level tailoring. In this review, we focus on the recent applications of these NCs to energy conversion reactions, including those involved in water splitting (hydrogen and oxygen evolution reactions), fuel cell operation (oxygen reduction and hydrogen oxidation reactions), and electrochemical CO2 reduction. Emblematic examples are used to highlight the roles of different NC parts, for example, core metal and surrounding ligands, and the significance of the electrode substrate. Finally, we discuss the perspectives of the future development and implementation of NC‐based energy conversion systems. This review examines the performances of atomically precise metal nanoclusters as the electrocatalysts of energy conversion reactions, namely water splitting, fuel cell, and CO2 conversion reactions, focusing on the strategies used to promote catalytic activity and discussing the future perspectives and resolution of the remaining challenges.