High-Performance Hydrogen Evolution Reaction Catalysts in Two-Dimensional Nodal Line Semimetals

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Chemistry

Background:

• Topological quantum catalysts (TQCs) are an emerging field, with most research focused on 3D materials.
• The potential of 2D topological semimetals as TQCs for catalytic applications, particularly the hydrogen evolution reaction (HER), remains underexplored.

Purpose of the Study:

• To investigate the potential of 2D topological semimetals as highly efficient topological quantum catalysts (TQCs).
• To explore the use of the Cu2Si monolayer as a superior TQC for the hydrogen evolution reaction (HER).
• To theoretically determine the HER performance of other 2D nodal line semimetals.

Main Methods:

• First-principles calculations were employed to analyze the electronic structure and catalytic properties.
• The Gibbs free energy of hydrogen adsorption (ΔGH*) was calculated to assess catalytic activity.
• The influence of nodal line positions relative to the Fermi level on catalytic activity was investigated.

Main Results:

• The Cu2Si monolayer exhibits two Γ-centered nodal lines (L1 and L2) in the k=0 plane.
• Cu2Si demonstrates a low Gibbs free energy (ΔGH*) of 0.195 eV for HER, comparable to platinum.
• The catalytic activity of HER is significantly affected by the position of nodal lines relative to the Fermi level.
• High HER performance was theoretically predicted for other 2D nodal line semimetals, including Ti3C2, Cr2S3, ScCl, and CuSe.

Conclusions:

• 2D nodal line semimetals, exemplified by Cu2Si, are promising topological quantum catalysts for the hydrogen evolution reaction.
• The presence and position of nodal lines are critical factors in determining the electrocatalytic efficiency.
• These findings pave the way for designing high-performance, non-noble metal HER catalysts on a 2D scale.