脱载体-声波散射提高了n型基Te材料的热电性能
De-Zhuang Wang1, Wei-Di Liu2,3, Yuanqing Mao4,5
1State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
Journal of the American Chemical Society
|January 5, 2024
概括
对n型GeTe材料的回火优化使颗粒变大,并产生空隙集群. 这会解载体和声子散射,显著提高热电性能.
科学领域:
- 材料科学
- 固态物理
- 热电器
背景情况:
- 在n型GeTe中,载体和声子散射限制热电性能.
- 解开这些分散机制对于提高效率至关重要.
研究的目的:
- 在n型GeTe中开发一种有效的分离载体-声子散射策略.
- 通过回火优化提高n型基于GeTe的材料的热电性能.
主要方法:
- 通过边界迁移优化回火时间以扩大粒度.
- 在回火过程中通过 Ge 空位聚合引发空位集群.
主要成果:
- 实现了扩大的粒度,减弱了载体散射.
- 诱导的空隙集群强化了声子散射,导致脱散射.
- 在Ge$_{0.67}$Pb$_{0.13}$Bi$_{0.2}$中获得了0.4的峰值值 (ZT).
结论:
- 扩大颗粒和空位集群在分离载体-声子散射中起着至关重要的作用.
- 化优化是制造高性能n型GeTe热电材料的可行方法.
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