皮尔尔斯扭曲作为In(4) Se(3-delta) 晶体中高热电性能的一种途径
Jong-Soo Rhyee1, Kyu Hyoung Lee, Sang Mock Lee
1Materials Research Laboratory, Samsung Advanced Institute of Technology, Yongin 446-712, Korea.
Nature
|June 19, 2009
概括
研究人员发现了一种新的热电材料,In{4) Se{3-delta),可以有效地将废热转化为电力. 这种材料由于独特的电荷密度波特性,具有高的热电功率 (ZT).
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 能源可持续性 能源可持续性
背景情况:
- 热电能收获将废热转化为电力,这对可持续性至关重要.
- 现有材料的低热电效率 (ZT) 阻碍了实际应用.
- 目前用于中温发电机的n型材料的ZT≤1,需要改进的替代品.
研究的目的:
- 识别和描述具有提高效率的新型n型热电材料.
- 调查负责高热电性能的潜在机制.
- 探索设计高ZT材料的新策略.
主要方法:
- 合成和表征的二元晶体材料In(4) Se(3-delta).
- 高分辨率传输电子显微镜 (HRTEM) 和电子衍射.
- 了解电子和热传输属性的第一原则计算.
主要成果:
- 在705K时为散装材料In(4) Se(3-delta) 实现了1.48的ZT值.
- 在材料中发现了电荷密度波 (CDW) 不稳定性.
- 与CDW相关的电气和热传输中观察到显著的异质性.
结论:
- 4) 3-delta) 材料表现出高的ZT值,超过目前的中温n型选项.
- 电荷密度波动不稳定性是材料优越热电性能的关键.
- 利用CDWs诱导的内在纳米结构性质为开发先进的热电材料提供了一个有前途的途径.
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