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DFT 基于WS2的纳米管在扭曲变形下电子性能的研究
Anton V Domnin1, Ilia E Mikhailov1, Robert A Evarestov1
1Quantum Chemistry Department, St. Petersburg State University, 7/9 Universitetskaya nab., 199034 St. Petersburg, Russia.
Nanomaterials (Basel, Switzerland)
|October 14, 2023
概括
扭曲变形显著影响合二硫化物 (WS2) 纳米管. 扭曲这些WS2纳米管减少了它们的带间距,从而有可能改善光催化活性.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术 纳米技术
背景情况:
- 硫化 (WS2) 纳米管是具有独特电子和机械性能的有希望的纳米材料.
- 了解WS2纳米管在变形下的机械行为对于其实际应用至关重要.
研究的目的:
- 为了研究扭曲变形对性WS2纳米管的结构和电子特性的影响.
- 探索纳米管直径和扭曲下的结构稳定性之间的关系.
- 评估扭曲变形的潜力,以调整WS2纳米管的电子特性和光催化活性.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 所有计算都使用了原子高斯式轨道的基础集.
- 模拟了不同直径的状WS2纳米管,特别是 (8,2), (12,3), (24,6) 和 (36,9).
主要成果:
- 较小直径的WS2纳米管表现出自发的结构变形,从它们最初的板配置.
- 扭曲变形导致WS2纳米管的带间隙显著减少.
- 带间隙缩小的程度取决于扭曲变形的程度.
结论:
- 较小直径纳米管的自发变形凸显了在理论研究中考虑结构放松的重要性.
- 扭曲变形提供了一个可行的途径来调整WS2纳米管的电子带间隙.
- 由于扭转而减少的带间隙表明光吸收增强,并有可能改善光催化应用.
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