Interface-Engineered 3D porous MoS₂-ReS₂ in-plane heterojunction as efficient hydrogen evolution reaction...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Two-dimensional materials offer potential for enhanced hydrogen evolution reaction (HER) catalysis.
• Constructing in-plane heterojunctions is crucial for maximizing interfacial density and catalytic activity.
• Challenges remain in fabricating stable and efficient HER catalysts for practical applications.

Purpose of the Study:

• To develop and characterize novel three-dimensional porous MoS₂-ReS₂ in-plane heterojunctions.
• To evaluate the electrocatalytic performance of these heterojunctions for the hydrogen evolution reaction (HER) in water splitting.
• To elucidate the underlying mechanisms responsible for the enhanced catalytic activity.

Main Methods:

• Fabrication of MoS₂-ReS₂ in-plane heterojunctions using chemical vapor deposition.
• Electrocatalytic performance testing for HER across a wide pH range, including alkaline seawater.
• Electrochemical stability testing up to 200 hours.
• Density functional theory (DFT) calculations to investigate interfacial electronic properties.

Main Results:

• The optimized MoS₂-ReS₂ heterojunction demonstrated superior HER performance compared to standalone MoS₂ and ReS₂.
• Achieved an overpotential of 200 mV to reach 10 mA cm^-2 in alkaline seawater.
• Exhibited remarkable electrochemical stability, lasting over 200 hours in alkaline seawater.
• DFT calculations revealed electron redistribution at the interface due to work function disparities, enhancing catalytic activity.

Conclusions:

• Three-dimensional porous MoS₂-ReS₂ in-plane heterojunctions are highly effective electrocatalysts for HER.
• Interfacial electron redistribution significantly contributes to enhanced water splitting efficiency.
• These findings provide a pathway for designing advanced, earth-abundant HER electrocatalysts for practical water electrolysis.