In-situ observation of structural evolution of single-atom catalysts: From synthesis to catalysis

Abstract

Atomically dispersed single-atom catalysts (SACs) have been extensively studied over the past decade because of their high atom utilization efficiencies and specific selectivities. Although numerous strategies have been proposed to obtain SACs with high densities and stabilities, the transformation mechanism that occurs during the reaction is still unclear. This review summarizes the structural evolution of SACs in the preparation process and reaction with various electron microscopy techniques at atomic scale under environmental conditions. Current state-of-the-art environmental electron microscopy studies on SACs mainly focus on porous carbons, metals or metal oxides, and some specific composite materials. The dynamic evolution of SACs under various reaction conditions is also investigated in this study. Finally, we highlight the challenges and drawbacks of the current studies and the prospects for the future exploration of SACs with environmental strategies.

Keywords

Single-atom catalysts / Structural transformation / Atomization / Environmental electron microscope

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

We would like to acknowledge funding support from the National Natural Science Foundation of China (52204255), Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization (PCSX202201), China Postdoctoral Science Foundation (2020M682764), and the Yangzhou University Start-up Foundation.

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