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Updated: May 23, 2025

Characterization of Thermal Transport in One-dimensional Solid Materials

Characterization of Thermal Transport in One-dimensional Solid Materials

Published on: January 26, 2014

通过化学结合工程实现内在的超低温和类似玻璃的热传输

Zhonghao Xia¹, Xingchen Shen^2,3, Jun Zhou⁴

¹Key Laboratory of Advanced Materials and Devices for Post-Moore Chips, Ministry of Education, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China.

Advanced science (Weinheim, Baden-Wurttemberg, Germany)

|March 7, 2025

概括

研究人员使用弱化学键设计了具有超低格子导热率的新材料. 这些新型化合物显示出先进的热管理和能源应用的潜力.

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:

具有玻璃状,低晶格导热率 (κL) 的晶体对于热屏障涂层,热电能转换和热管理具有价值.
这种特性通常在含有重元素的化合物,大型单元细胞或在高温下发现.

研究的目的:

探索化学结合原理以削弱Ag-Ag结合并增强基于Ag6-八面体的化合物中的晶格不和性.
通过化学结合工程设计和识别具有超低导热率的新型化合物.

主要方法:

利用化学结合原理来削弱Ag-Ag键并增强格子的无和性.
纳入了素离子作为桥梁连接体,以促进声子声.
理论上确定了五种基于八面体的Ag6化合物 (AAg3X2,A = Li,Na,K;X = S,Se) 具有低平均原子质量和强烈的四声散射.

主要成果:

已识别的化合物具有超低的导热率 (0.30.6 W m−1 K−1),温度依赖性最小 (T−0.1).
实验验证证证了NaAg3S2在200550 K之间0.45 W m-1 K-1的 κL.
由于微弱的化学键和低的平均原子质量,证明了强烈的四声波散射.

结论:

微弱的化学结合对于设计具有玻璃状晶格导热性的材料至关重要.
化学结合工程是一种有效的策略,可以实现所需的热传输特性.
已确定的基于八面体的Ag6化合物代表了先进的热管理应用的有希望的候选者.

关键词:

化学结合原理化学结合原理网格热导电性网格热导电性材料设计和发现.固态化学固态化学

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