Boosting hydrogen evolution on MoS₂ via co-confining selenium in surface and cobalt in inner layer

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical hydrogen evolution reaction (HER) is crucial for hydrogen production, but hindered by inefficient and costly catalysts.
• Molybdenum disulfide (MoS2) is a low-cost material with potential for HER, yet it suffers from limited catalytic performance.

Purpose of the Study:

• To develop a highly efficient and inexpensive catalyst for large-scale electrochemical hydrogen evolution reaction (HER).
• To enhance the catalytic activity of MoS2 by co-confining selenium and cobalt within its tri-layer structure.

Main Methods:

• Fabrication of a MoS2 nanofoam catalyst incorporating surface-confined selenium and inner-layer-confined cobalt.
• Electrochemical testing to evaluate HER activity at high current densities.
• First-principles calculations to elucidate the catalytic mechanism and active site origins.

Main Results:

• The engineered MoS2 nanofoam catalyst exhibits ultra-high HER activity at a current density of 1000 mA cm⁻².
• Achieved an overpotential of 382 mV, significantly lower than commercial Pt/C (671 mV), with stable performance for 360 hours.
• Calculations reveal synergistic effects of cobalt and selenium in creating numerous active sites with optimized hydrogen adsorption.

Conclusions:

• The developed MoS2 nanofoam catalyst offers superior HER performance, overcoming limitations of existing heteroatom-doped MoS2 materials.
• The strategy of co-confining heteroatoms provides a viable pathway for designing advanced MoS2-based catalysts for industrial HER applications.