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Enhanced Hydrogen Evolution Reactivity of T'-Phase Tungsten Dichalcogenides (WS₂, WSe₂, and WTe₂) Materials: A DFT Study.

ABSTRACT: The hydrogen evolution reaction (HER) plays a crucial role in hydrogen gas production. Layers of transition-metal dichalcogenides (TMDs) possess adjustable electronic structures, and TMDs with H-phase structures have been proposed as substitute HER catalysts. Nonetheless, there are few systematic theoretical analyses of the HER catalytic properties of TMDs with T'-phase structures. Using a DFT calculation, we investigated the electrocatalytic properties of W-based dichalcogenides (WS₂, WSe₂, and WTe₂) through defect engineering. It was found that the interaction of H atoms with the basal plane can be tuned using non-metallic atomic doping, especially with P, thereby enhancing catalytic activity. Furthermore, the computation results demonstrated that high P-doping concentrations can enhance the number of active sites and exhibit a suitable ΔG_H*.

SUBMITTER: Huang H

PROVIDER: S-EPMC9569713 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Enhanced Hydrogen Evolution Reactivity of T'-Phase Tungsten Dichalcogenides (WS2, WSe2, and WTe2) Materials: A DFT Study.

Huang Haihua H Hu Guowei G Hu Chengchao C Fan Xiaofeng X

International journal of molecular sciences 20221003 19

The hydrogen evolution reaction (HER) plays a crucial role in hydrogen gas production. Layers of transition-metal dichalcogenides (TMDs) possess adjustable electronic structures, and TMDs with H-phase structures have been proposed as substitute HER catalysts. Nonetheless, there are few systematic theoretical analyses of the HER catalytic properties of TMDs with T'-phase structures. Using a DFT calculation, we investigated the electrocatalytic properties of W-based dichalcogenides (WS2 ...[more]

PMID: 36233027

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