Nickel sulfide (Ni3S2) is a promising hydrogen evolution reaction (HER) catalyst by virtue of its metallic electrical conductivity and excellent stability in alkaline medium. However, the reported catalytic activities for Ni3S2are still relatively low. Herein, an effective strategy to boost the H adsorption capability and HER performance of Ni3S2through nitrogen (N) doping is demonstrated. N‐doped Ni3S2nanosheets achieve a fairly low overpotential of 155 mV at 10 mA cm−2and an excellent exchange current density of 0.42 mA cm−2in 1.0
Molybdenum sulfide (MoS2) has emerged as a promising electrocatalyst for hydrogen evolution reaction (HER) owing to its high activity and stability during the reaction. However, the efficiency of hydrogen production is limited by the number of active sites in MoS2. In this work, a simple method of fabricating polycrystalline multilayer MoS2on Mo foil for efficient hydrogen evolution is demonstrated by controlling the sulfur (S) vacancy concentration, which can introduce new bands and lower the hydrogen adsorption free energy (Δ
- NSF-PAR ID:
- 10030911
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 4
- Issue:
- 16
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract m KOH electrolyte. The mass activity of 16.9 mA mg−1and turnover frequency of 2.4 s−1obtained at 155 mV are significantly higher than the values reported for other Ni3S2‐based HER catalysts, and comparable to the performance of best HER catalysts in alkaline medium. These experimental data together with theoretical analysis suggest that the outstanding catalytic activity of N‐doped Ni3S2is due to the enriched active sites with favorable H adsorption free energy. The activity in the Ni3S2is highly correlated with the coordination number of the surface S atoms and the charge depletion of neighbor Ni atoms. These new findings provide important guidance for future experimental design and synthesis of optimal HER catalysts. -
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