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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Vacancy complexes in carbon and boron nitride nanotubes
M G Mashapa1, N Chetty, S Sinha Ray
1Physics Department, University of Pretoria, Pretoria, 0001, South Africa.
Journal of Nanoscience and Nanotechnology
|February 21, 2013
Summary
Divacancies significantly alter carbon and boron nitride nanotubes
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Carbon and boron nitride nanotubes exhibit unique electronic and structural properties.
- Defects, such as divacancies, can profoundly influence nanotube characteristics.
- Understanding defect behavior is crucial for tailoring nanotube applications.
Purpose of the Study:
- To investigate the impact of various divacancies on carbon and boron nitride nanotubes.
- To analyze the stability, structural, and electronic property changes induced by these defects.
- To elucidate the mechanisms behind electronic property modifications.
Main Methods:
- Ab initio density functional theory calculations were employed.
- The study focused on different divacancy configurations (e.g., V(B)B(N), V(N)N(B), V(C)V(C)).
- Stability, relaxation energies, and electronic band structures were computed.
Main Results:
- Specific divacancies show preferential stability under boron-rich or nitrogen-rich conditions.
- Stoichiometric divacancies (V(B)V(N), V(B)C(N), V(N)C(B)) are stable in both environments.
- Divacancies introduce energy levels within the band gap, drastically altering electronic properties.
- Band gap reduction or complete removal was observed in semiconducting nanotubes.
Conclusions:
- Divacancies are key to tuning the electronic properties of nanotubes.
- The type and configuration of divacancies dictate their stability and impact.
- These findings offer insights for designing functionalized nanotubes with specific electronic behaviors.
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