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Intrinsic point defects in buckled and puckered arsenene: a first-principles study
K Iordanidou1, J Kioseoglou, V V Afanas'ev
1Department of Physics and Astronomy, University of Leuven, B-3001 Leuven, Belgium. konstantina.iordanidou@kuleuven.be.
Physical Chemistry Chemical Physics : PCCP
|March 30, 2017
Summary
Point defects like Stone-Wales and vacancies significantly alter arsenene
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Chemistry
Background:
- Two-dimensional materials like arsenene offer unique electronic properties.
- Understanding point defects is crucial for tailoring material performance.
- Arsenene's buckled and puckered phases present distinct structural characteristics.
Purpose of the Study:
- Investigate the impact of point defects on arsenene's structural, energetic, and electronic properties.
- Determine the stability and influence of Stone-Wales defects and vacancies.
- Analyze the effect of hydrogen passivation on defective arsenene.
Main Methods:
- First-principles calculations were employed to model defect behavior.
- Structural, energetic, and electronic properties were systematically computed.
- The influence of a hydrogen-rich environment was simulated.
Main Results:
- Stone-Wales defects are thermodynamically favorable and stable at room temperature.
- Single vacancies create mid-gap states; Stone-Wales and di-vacancies induce strain-related states near band edges.
- Di-vacancy defects in the puckered phase exhibit less band structure disruption than in the buckled phase.
- Hydrogen termination of vacancies is exothermic and eliminates defect-induced gap states.
Conclusions:
- Point defects profoundly influence arsenene's electronic properties, particularly in the buckled phase.
- The type and location of defects dictate their impact on electronic structure.
- Hydrogen passivation offers a viable strategy to mitigate defect-induced electronic perturbations in arsenene.
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