在范德瓦尔斯结构中通过旋转 (失序) 调整横平面格子导热率
Fredrik Eriksson1, Erik Fransson1, Christopher Linderälv1
1Department of Physics, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
ACS nano
|December 8, 2023
概括
在像MoS2,C和BN这样的二维材料中引入旋转障碍,大大降低了透平面导热率. 这一发现为电子产品的热管理提供了新的途径.
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) 材料具有独特的热性能.
- 二硫化物 (MoS2) 具有不规则的间层旋转,在晶格导热率 (LTC) 中表现出极端的异质性.
- 这种异质性与集成电路中的废热管理有关.
研究的目的:
- 调查影响LTC的旋转障碍原理是否延伸到其他2D材料.
- 探索旋转失调和秩序对通过平面和平面内LTC的影响.
- 确定LTC观察到的变化背后的机制,并为最小的LTC找到最佳条件.
主要方法:
- 原子级模拟利用机器学习的潜力.
- 分析摩埃尔结构中旋转失调和特定扭转角度的影响.
- 调查LTC,横向声学模式和堆叠障碍之间的相关性.
主要成果:
- 引入旋转障碍将通过平面的LTC驱动到MoS2,C和BN的玻璃极限,而在平面内的LTC基本保持不变.
- 超低透平面LTC与横向声学模式在透平面方向的崩有关.
- 摩埃尔结构中的扭转角度有效调整透平面LTC,最小的LTC在1-4°的角度实现,最显著的是MoS2.
结论:
- 旋转障碍是各种2D材料中实现极低透平面导热率的关键因素.
- 堆叠障碍的程度,通过简单的描述符可预测,与最小LTC的最佳扭转角度相关.
- 这些发现为设计具有针对先进应用的量身定制的热传输特性的二维材料提供了一条途径.
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