Interface-Engineered NiSe₂/1T-Phase-Rich MoS₂ Heterostructures for Enhanced Electrocatalytic Hydrogen Evolution.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Heterojunctions of 2D materials can enhance catalytic activity.
• Phase engineering is a key strategy for improving non-noble metal catalysts.
• The hydrogen evolution reaction (HER) is crucial for water electrolysis.

Purpose of the Study:

• To demonstrate an in situ phase engineering strategy for MoS2.
• To enhance HER performance through heterointerface coupling with NiSe2.
• To elucidate interfacial charge transfer dynamics using DFT calculations.

Main Methods:

• In situ phase engineering of MoS2.
• Heterointerface coupling with NiSe2.
• Density functional theory (DFT) calculations.
• Electrocatalytic performance testing for HER.

Main Results:

• Optimized MoS2@NiSe2/CC-2 electrocatalyst achieved 98 mV overpotential at 10 mA cm-2.
• A favorable Tafel slope of 91 mV dec-1 was recorded.
• Interfacial charge transfer dynamics were elucidated, explaining enhanced HER.

Conclusions:

• Phase engineering combined with heterointerface coupling significantly boosts HER performance.
• The MoS2@NiSe2 system provides a universal design principle for efficient HER electrocatalysts.
• Precise interface modulation is key for developing advanced electrocatalysts.