Nitrogen plasma engineered MoS₂ for catalyzing hydrogen evolution reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Monolayer molybdenum disulfide (ML-MoS2) shows promise for electrocatalysis due to its electrical properties and surface area.
• However, inert basal planes and limited active edge sites hinder its catalytic efficiency.

Purpose of the Study:

• To activate the basal plane of ML-MoS2 for improved hydrogen evolution reaction (HER) catalysis.
• To develop a scalable method for enhancing the performance of 2D transition-metal dichalcogenides.

Main Methods:

• Remote nitrogen (N)-plasma treatment to incorporate N into ML-MoS2.
• Experimental and theoretical analyses to understand the mechanism of HER enhancement.

Main Results:

• Optimized N-doped ML-MoS2 achieved an overpotential of 348 mV at 10 mA cm-2 and a Tafel slope of 94 mV·dec-1.
• Nitrogen incorporation induced lattice defects, altered charge distribution, and increased active-site density.
• Demonstrated enhanced HER activity attributed to surface activation.

Conclusions:

• Remote N-plasma treatment is an effective strategy for activating the basal plane of ML-MoS2.
• This approach offers a scalable route for tuning the catalytic performance of 2D materials for HER.
• The findings pave the way for advanced electrocatalyst design.