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The optimization of traditional electrocatalysts has reached a point where progress is impeded by fundamental physical factors including inherent scaling relations among thermokinetic characteristics of different elementary reaction steps, non‐Nernstian behavior, and electronic structure of the catalyst. This indicates that the currently utilized classes of electrocatalysts may not be adequate for future needs. This study reports on synthesis and characterization of a new class of materials based on 2D transition metal dichalcogenides including sulfides, selenides, and tellurides of group V and VI transition metals that exhibit excellent catalytic performance for both oxygen reduction and evolution reactions in an aprotic medium with Li salts. The reaction rates are much higher for these materials than previously reported catalysts for these reactions. The reasons for the high activity are found to be the metal edges with adiabatic electron transfer capability and a cocatalyst effect involving an ionic‐liquid electrolyte. These new materials are expected to have high activity for other core electrocatalytic reactions and open the way for advances in energy storage and catalysis.
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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 Manuscript
- Journal Article:
- https://doi.org/10.1039/d0ee01714k
