隐藏结构:实现低导热率和高热电性能的驱动因素
Debattam Sarkar1, Animesh Bhui1, Ivy Maria1
1New Chemistry Unit, School of Advanced Materials and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bangalore 560064, India. kanishka@jncasr.ac.in.
Chemical Society reviews
|May 8, 2024
概括
晶体固体中的局部原子结构显著抑制热传输,模仿玻璃般的导热性. 了解这些现象是开发具有低导热性的先进热电材料的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 热力学是一种热力学.
背景情况:
- 固体中的晶格导热率 (κ lat) 取决于原子的排列和温度.
- 晶体固体通常具有比玻璃更高的导热率,这是由于更长的声子平均自由路径.
- 晶体中的类似玻璃的热传输对热电应用具有根本性的兴趣和关键.
研究的目的:
- 审查具有本质低导热性的晶体固体的状态.
- 探索局部结构现象在调节音声动态中的作用.
- 突出先进的表征技术和设计低 κ lat. 的材料的新策略.
主要方法:
- 对热传输基本原理的审查.
- 对影响声子散射的局部结构现象的分析.
- 讨论先进的亚原子水平表征技术.
- 检查热电材料中的结构热导电关系.
主要成果:
- 局部不对称的原子图案 (例如,偏离中心,声) 极大地扰乱了声子传输.
- 这些亚斯特罗姆尺度现象通常被传统晶体学所忽视.
- 晶体固体的低导热率经常与这些局部结构特征有关.
结论:
- 局部结构工程是一种有前途的策略,可以在晶体固体中实现低晶格导热率.
- 了解和控制当地的原子安排对于优化热电材料至关重要.
- 需要进一步的研究,整合先进的表征,理论和合成,以实现高性能热电.
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