在Zintl型TlInTe2中引发的内在雷特勒低导热
Manoj K Jana, Koushik Pal, Avinash Warankar1
1Department of Chemistry, Indian Institute of Science Education and Research (IISER) , Pune 411008, India.
Journal of the American Chemical Society
|March 7, 2017
概括
二化 (TlInTe2) 由于离子的动,具有超低的导热性. 这种独特的网格动态是设计先进热电材料的关键.
科学领域:
- 材料科学
- 固态物理
- 凝聚物质物理学
背景情况:
- 了解化学结合和晶格动态对于设计具有超低导热性的晶体固体至关重要.
- 这些材料对于热电等应用是必不可少的.
研究的目的:
- 为了研究印二化物 (TlInTe2) 的低晶格导热性.
- 阐明离子在声子运输中的动态作用.
主要方法:
- 实验测量包括热容量和THz时间域光谱.
- 分析结合,格子动态和声子相互作用的第一原理计算.
主要成果:
- TlInTe2 具有非常低的晶格导热率 (大约 0.5 W/mK) 在室温附近.
- 弱结的Ti离子在c轴上表现出动态,由静电排斥驱动.
- 观察到与Tl摇相关的低频爱因斯坦模式.
- 第一个原则的计算显示了Tl-rattler振动和声波之间的强合.
结论:
- 离子的动力学是TlInTe2超低导热率的主要机制.
- 这项研究提供了对具有摇摇欲的客原子的材料中的声子运输机制的见解.
- 这些发现支持基于声诱导的声子散射的新型热电材料的设计.
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