Revealing the Synergy Among Single‐Atoms, Clusters and Nanoparticles by In Situ Methods for Efficient Electrocatalysis

Abstract Nanoparticles/clusters and single‐atoms coupled catalysts have shown superior electrocatalytic performances due to the synergy between different active sites. Revealing the synergistic effects of coupled catalysts by in situ characterization is crucial for rational catalyst design. This review systematically summarizes in situ methods for investigating energy conversion‐related reactions of coupled catalysts. A brief description of the different in situ methods and synthetic strategies for coupled catalysts is first provided. Next, the coupled catalysts during the hydrogen evolution reaction, hydrogen oxidation reaction, oxygen evolution reaction, oxygen reduction reaction, alcohol oxidation reaction, and carbon dioxide reduction reaction, investigated using in situ methods, are presented. Finally, some suggestions are provided for the further design of highly efficient coupled catalysts and for exploring the structure‐property relationships. It is hoped that this review will further stimulate research interest in nanoparticles, clusters, and single‐atoms coupled catalysts, as well as in situ characterization techniques.