Computational Screening toward Hydrogen Evolution Reaction by the Introduction of Point Defects at the Edges of Group...

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Developing efficient electrocatalysts for the hydrogen evolution reaction (HER) is crucial for clean hydrogen energy production.
• Surface defects on catalysts play a vital role in enhancing catalytic activity.

Purpose of the Study:

• To investigate the HER performance of group IVA monochalcogenides (MXs) with M/X point defects on their edges.
• To identify specific defect configurations that optimize HER activity.

Main Methods:

• Computational evaluation of HER performance for various MX materials (GeS, GeSe, SnSe) with edge point defects.
• Analysis of the relationship between Gibbs free energy of hydrogen adsorption (ΔG_H*) and p-band centers.
• Assessment of catalyst stability using vacancy-formation energy and strain engineering.

Main Results:

• The GeS edge with a Ge vacancy (ΔG_H* = 0.016 eV), GeSe edge with a Se vacancy (ΔG_H* = 0.073 eV), and SnSe edge with a Sn vacancy (ΔG_H* = -0.037 eV) exhibited superior HER performance.
• These defect-engineered materials showed HER activity comparable to or exceeding that of platinum.
• A correlation between ΔG_H* and p-band centers was established.

Conclusions:

• Introduction of point defects at the edges of MX materials significantly boosts their HER performance.
• These defect-engineered monochalcogenides show great promise as efficient electrocatalysts for hydrogen production and energy storage.
• The findings provide a pathway for designing novel catalysts for clean energy applications.