关于不同菌株类型下单层h-BN光电性能的第一原则研究
ShaoRong Li1, Hao Wang2, ChengYue Wang3,4
1College of Science, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, People's Republic of China. 404840127@qq.com.
Journal of molecular modeling
|January 31, 2024
概括
应变显著影响单层六角化 (h-BN) 的性能. 双轴应变对机械,电子和光学特征的影响比单轴应变更大,带隙在应变下缩小.
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:
- 二维 (2D) 材料是由于其独特的光电子和化学特性而迅速发展的领域.
- 这些材料对场效应装置的应用具有显著的前景.
- 六角化 (h-BN) 是一个具有显著特征的关键二维材料.
研究的目的:
- 研究单轴和等轴应变对单层h-BN.机械,电子和光学性能的影响.
- 为了比较双轴与单轴应变对h-BN基本性质的影响.
- 了解潜在的设备应用的应变诱导的修改.
主要方法:
- 基于密度函数理论 (DFT) 的第一原则计算,使用VASP软件.
- 使用投影机增强波 (PAW) 伪潜力和在通用梯度近似 (GGA) 中的Perdew-Burke-Ernzerhof (PBE) 函数.
- 采用了15 Å的真空层,9×9×1的Monkhorst-Pack k点网格,500 eV的能量切断,以及特定的能量和力的融合标准.
主要成果:
- 压缩应变严重影响单层h-BN的稳定性.
- 单层h-BN的带隙随着应变的增加而缩小.
- 拉力和压力应变都会导致光学性能的相对变化,双轴应变对机械,电子和光学性能的影响比单轴应变更大.
结论:
- 应变工程是一种可行的方法来调整单层h-BN的特性.
- 与单轴菌株相比,双轴菌株对h-BN的特征具有更明显的影响.
- 这些发现为设计基于新二维材料的电子和光学设备提供了洞察力.
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