在压缩碳相中的异常热传输
Zefang Ye1, Janghan Park1, Yongjian Zhou1
1Walker Department of Mechanical Engineering, <a href="https://ror.org/00hj54h04">The University of Texas at Austin</a>, Austin, Texas 78712, USA.
Physical review letters
|December 3, 2024
概括
压缩应变极大地改变了碳.
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
- 固态化学 固态化学
背景情况:
- 像石墨烯这样的碳材料具有独特的特性,例如超导电性和异性热导电性.
- 压力应变对碳的导热性和相变的影响尚不清楚.
研究的目的:
- 为了研究压缩石墨相的现场高压导热性.
- 探索应变诱导的结构转变和碳中的热传输之间的关系.
主要方法:
- 利用皮秒短暂的热反射强度在高压下进行现场导热性测量.
- 运用第一原则计算来建模物质行为.
- 进行了互补的现场拉曼光谱和X射线衍射分析.
主要成果:
- 观察到异常的导热率在260W/mK达到峰值,约为15-20GPa.
- 在大约35GPa时,热导率显著下降到3.0W/mK.
- 将这些变化与层间曲和sp2到sp3结合过渡相关联.
结论:
- 异常的导热率是由声子传输所驱动的,受结构和结合变化的影响.
- 形成M碳纳米晶体和无形碳相有助于观察到的趋势.
- 应变工程为调整碳材料的热和机械性能提供了一条途径.
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