Recent Progress in and Future Perspectives on High-Density Single-Atom Electrocatalysts

Abstract

Abstract

Single-atom catalysts (SACs) exhibit tremendous potential in electrocatalysis because of their high intrinsic activity and remarkable selectivity arising from their tunable electronic structures and maximal atom utilization. A high density of SACs is fundamental for enhancing the activity and durability during electrochemical reactions. In this review, we first summarize the leading strategies for the synthesis of metal single-atom electrocatalysts and the use of machine learning in the design and screening of SACs, with a focus on maximizing the metal loading through deliberate temperature control, followed by the application of such high-loading SACs to a range of important reactions in electrochemical energy technologies, such as the oxygen reduction reaction (ORR), H₂O₂ electrosynthesis, the oxygen evolution reaction (OER), the hydrogen evolution reaction (HER), the carbon dioxide reduction reaction (CO₂RR), the nitrate reduction reaction (NO₃RR), and the reactions in lithium-sulfur batteries. The review concludes with a perspective highlighting the key challenges and future research directions in the development and application of high-density SACs.

Graphical Abstract

High-density metal sites are crucial for enhancing the performance of single-atom catalysts (SACs) during electrocatalytic reactions. This review systematically summarizes the principal synthesis strategies for high-density SACs, outlines the application of machine learning-assisted designing and screening SACs, and discusses their applications in electrocatalytic energy storage and conversion systems.

Keywords

Single-atom catalysts / High-density sites / High-temperature pyrolysis / Low-temperature synthesis / Electrocatalysis

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Funding

Xiangtan University Scientific Research Project Funding(22QDZ51)

Natural Science Foundation of Hunan Province(2024JJ6421)

National Science Foundation(CHE-1900235)

RIGHTS & PERMISSIONS

The Author(s)