VS₂: an efficient catalyst for an electrochemical hydrogen evolution reaction in an acidic medium

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Efficient electrocatalysts are crucial for energy conversion technologies like hydrogen production.
• Developing scalable, cost-effective synthesis methods for advanced materials remains a challenge.

Purpose of the Study:

• To develop an eco-friendly, cost-effective, single-step method for scalable synthesis of VS2 and VS4/rGO composite.
• To evaluate the electrocatalytic performance of VS2 and VS4/rGO for the hydrogen evolution reaction (HER).

Main Methods:

• Scalable synthesis of VS2 and VS4/rGO composite using a single-step method.
• Electrocatalytic performance testing for HER in 0.1 M H2SO4.
• Analysis of electrochemical active surface area, crystal structure, Tafel slope, and onset potential.

Main Results:

• VS2 exhibited superior catalytic performance for HER compared to VS4/rGO, attributed to its larger electrochemical active surface area and hexagonal crystal lattice.
• The VS2 modified electrode showed remarkable stability over 10h and 43h of continuous electrolysis with negligible overpotential change.
• Low Tafel slope (36 mV dec-1) and onset potential (15 mV vs. RHE) were observed for VS2, indicating efficient catalysis.
• Preliminary photoelectrochemical studies showed a significant decrease in charge transfer resistance for VS2 under illumination.

Conclusions:

• The developed single-step synthesis method provides an efficient route for scalable VS2 production.
• VS2 is a highly promising electrocatalyst for hydrogen evolution reactions, offering excellent activity, stability, and durability.
• VS2 demonstrates potential for photoelectrochemical applications due to reduced charge transfer resistance under light.