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Abstract Single atoms of select transition metals supported on carbon substrates have emerged as a unique system for electrocatalysis because of maximal atom utilization (≈100%) and high efficiency for a range of reactions involved in electrochemical energy conversion and storage, such as the oxygen reduction, oxygen evolution, hydrogen evolution, and CO2reduction reactions. Herein, the leading strategies for the preparation of single atom catalysts are summarized, and the electrocatalytic performance of the resulting samples for the various reactions is discussed. In general, the carbon substrate not only provides a stabilizing matrix for the metal atoms, but also impacts the electronic density of the metal atoms due to strong interfacial interactions, which may lead to the formation of additional active sites by the adjacent carbon atoms and hence enhanced electrocatalytic activity. This necessitates a detailed understanding of the material structures at the atomic level, a critical step in the construction of a relevant structural model for theoretical simulations and calculations. Finally, a perspective is included highlighting the promises and challenges for the future development of carbon‐supported single atom catalysts in electrocatalysis.
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Two-dimensional nonlayered materials for electrocatalysis
Creating two-dimensional (2D) geometry from nonlayered catalytic materials may significantly advance electrocatalyst design. The 2D morphology of three-dimensional lattices (2D nonlayered materials) offer large structural distortions, massive surface dangling bonds, and coordinated-unsaturated surface atoms, which can induce high surface chemical activity and promote the chemisorption of reactants and fast interfacial charge transfer, thereby enhancing the electrocatalytic performance. In this article, we review typical strategies for structural engineering and manipulation of electronic states to enable the unique electrocatalytic advantages of 2D nonlayered materials. An overview is presented on recent research advances in the development of 2D nonlayered materials for catalyzing the representative electrochemical reactions that are essential to energy and sustainability, including hydrogen evolution, oxygen evolution, oxygen reduction, and CO 2 reduction. For each type of redox reactions, their unique catalytic performance and underlying mechanism are discussed. Important achievements and key challenges are also discussed.
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- Award ID(s):
- 1709025
- PAR ID:
- 10300932
- Date Published:
- Journal Name:
- Energy & Environmental Science
- Volume:
- 13
- Issue:
- 11
- ISSN:
- 1754-5692
- Page Range / eLocation ID:
- 3993 to 4016
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d0ee01714k
