The development of non‐noble metal materials for efficient hydrogen evolution reaction (HER) in wide pH range is still a challenge at present. Herein, a predesigned polyoxometalate (POM)‐based metal–organic polymer {L3Co2 · 6H2O}[H3GeMo12O40] · 9H2O (L = 1,2,4‐triazole) is employed as bimetallic source together with thiourea converting to CoS2@MoS2on carbon cloth (CC) (abbreviated to CoS2@MoS2@CC) for the first time. Impressively, the CoS2@MoS2in the form of vertically interconnected nanoarrays with multiple interfaces are grown in situ on CC and act as electrodes directly for HER. The CoS2@MoS2@CC‐30h composite exhibits superb activity and long‐durability in both acidic and alkaline media. Low overpotential is achieved in 0.5
1T-MoS2and single-atom modified analogues represent a highly promising class of low-cost catalysts for hydrogen evolution reaction (HER). However, the role of single atoms, either as active species or promoters, remains vague despite its essentiality toward more efficient HER. In this work, we report the unambiguous identification of Ni single atom as key active sites in the basal plane of 1T-MoS2(Ni@1T-MoS2) that result in efficient HER performance. The intermediate structure of this Ni active site under catalytic conditions was captured by in situ X-ray absorption spectroscopy, where a reversible metallic Ni species (Ni0) is observed in alkaline conditions whereas Ni remains in its local structure under acidic conditions. These insights provide crucial mechanistic understanding of Ni@1T-MoS2HER electrocatalysts and suggest that the understanding gained from such in situ studies is necessary toward the development of highly efficient single-atom decorated 1T-MoS2electrocatalysts.
more » « less- Award ID(s):
- 1654140
- NSF-PAR ID:
- 10184444
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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