在n型PbTe-Cu2中协同优化Phonon和载体运输的Cu的显著作用
1School of Materials Science and Engineering, Beihang University , Beijing 100191, China.
Journal of the American Chemical Society
|November 29, 2017
概括
在n型化物 (PbTe) 中实现高热电性能至关重要. 这项研究引入了铜化物 (Cu2Te) 含量,通过优化电热性能,显著提高了热电效率.
科学领域:
- 材料科学
- 固态物理
- 纳米技术
背景情况:
- 高性能的n型 telluride (PbTe) 热电材料对于补充现有的p型对应材料至关重要.
- 目前的n型PbTe材料在实现具有竞争力的热电性能方面面临挑战.
研究的目的:
- 为了提高n型PbTe的热电性能.
- 研究引入铜化物 (Cu2Te) 对PbTe热电性能的影响.
主要方法:
- 将Cu2Te纳入PbTe矩阵
- 结构性,电气性和热传输性能的系统性表征.
- 分析铜原子和沉物在调节热电性能中的作用.
主要成果:
- 在723K的温度下达到最高功率 (ZT) ~1.5,在300-873K的温度范围内达到创纪录的平均ZT>1.0.
- 证明了晶格导热率的协同抑制到0.38 Wm-1K-1.
- 由于铜对Pb空隙和间隙的影响,观察到载体移动性和功率因子的显著增强 (~37μW cm-2K-2在423K).
结论:
- 引入Cu2Te是同时增强n型PbTe电气和热传输特性的一种有效策略.
- 这项研究为开发高性能n型热电材料提供了可行的途径.
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