Structural and electronic properties of hydrogenated GaBi and InBi honeycomb monolayers with point defects

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Hydrogenated GaBi and InBi monolayers are emerging 2D materials with potential electronic applications.
• Understanding point defects is crucial for tailoring their properties.

Purpose of the Study:

• To systematically investigate the structural and electronic properties of point defects in hydrogenated GaBi and InBi monolayers.
• To explore the impact of vacancies, antisites, and Stone-Wales defects on electronic band structure.

Main Methods:

• First-principles calculations were employed to model and analyze defect configurations.
• Electronic properties, including bandgap and spin splitting, were computed.

Main Results:

• Perfect H2-Ga(In)Bi monolayers are semiconductors with small bandgaps (0.241 eV for GaBi, 0.265 eV for InBi).
• Ga(In) vacancies, Ga(In)-on-Bi antisites, and In-on-Bi antisites induce a metallic state.
• Other defects tune bandgaps between 0.09 eV and 0.3 eV, with SW defects decreasing the bandgap.
• Neighboring atom exchange preserves spin splitting while increasing the bandgap.

Conclusions:

• Point defects offer a versatile route to engineer the electronic properties of hydrogenated GaBi and InBi monolayers.
• Defect engineering can transform semiconductors into metals or precisely tune their bandgaps for specific applications.