高载波移动性和N型PbSe晶体热电模块的有希望的性能
Siqi Wang1, Yi Wen1, Yingcai Zhu1
1School of Materials Science and Engineering, Beihang University, Beijing, 100191, China.
Small (Weinheim an der Bergstrasse, Germany)
|April 19, 2024
概括
研究人员探索了用于热电模块的化 (PbSe),作为稀缺 bismuth telluride 的替代品. 轻型素兴奋剂显著改善了载体的移动性和热电性能,显示了具有成本效益的冷却应用的前景.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 热电学是一种热电学.
背景情况:
- 基于化物 (Bi2Te3) 的模块受到稀缺的限制.
- 化物 (PbSe) 提供了作为替代热电材料的潜力.
- 提高载体移动性是提高PbSe热电性能的关键.
研究的目的:
- 通过提高载体移动性来研究PbSe的热电潜力.
- 为高性能热电模块优化PbSe.
- 为Bi2Te3热电器件开发具有成本效益的替代品.
主要方法:
- 使用温度梯度方法培养大型PbSe晶体,以最大限度地降低谷物边界效应.
- 使用素 (Cl/Br/I) 应用光剂,以增加载体的移动性.
- 描述了热电特性,包括功率因子,热导率和ZT值.
主要成果:
- 在室温下实现了~1600 cm^2 V^-1 s^-1 的载体流动性,采用轻素合剂.
- 在300K时获得了~40μWcm^-1K^-2的高功率系数.
- 由于素兴奋剂的作用,显著降低了导热率和抑制了双极扩散.
- 在300K时达到0.6~,在773K时达到1.2~的PbSe-Br.峰值.
- 在300-773 K. 实现了~1.0的平均ZT (ZTave).
- 在PbSe单脚模块中证明了~5.8%的发电效率.
结论:
- 轻型素合剂和优化的晶体生长增强了PbSe中的载体移动性和热电性能.
- 聚乙烯表现出极好的热电特性,特别是在更高的温度下,具有具有具有成本效益的应用潜力.
- 基于PbSe的热电模块显示出作为可行替代Bi2Te3用于冷却和发电的可行替代方案.
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