建立Seebeck系数的黄金范围以最大化热电性能
Min Hong1,2, Wanyu Lyu1, Yuan Wang1
1Centre for Future Materials , University of Southern Queensland , Springfield , Queensland 4300 , Australia.
Journal of the American Chemical Society
|January 16, 2020
概括
研究人员确定了热电半导体的最佳Seebeck系数范围. 这一发现有助于最大限度地提高热电性能和开发高效的热电材料.
科学领域:
- 材料科学
- 固态物理
- 凝聚物质物理学
背景情况:
- 热电性质是合的,需要费米级优化以提高性能.
- 载体度是费米水平的常规代理,但随着有效质量的变化而变化,使优化变得复杂.
- 需要采用数据驱动的方法,以制定更明确的热电材料优化指南.
研究的目的:
- 建立一个目标Seebeck系数范围,以最大限度地提高热电半导体的优点.
- 用Bi替代研究n型PbSe材料的热电性质.
- 将微观结构特征与热电性能相关联.
主要方法:
- 大数据调查以确定最佳的热电参数.
- 电子显微镜 (例如TEM,SEM) 用于微观结构分析.
- 测量西贝克系数,载体度和热导率.
主要成果:
- 对于具有0.4-1.5 W m-1 K-1的半导体,确定了一个金色的Seebeck系数范围 (202-230 μV K-1).
- 在Pb1−xBixSe中高密度的位移和孔隙有助于低晶格导热.
- 比替代有效调整了西贝克系数,达到接近黄金范围的值 (Pb0.98Bi0.02Se中的-230μV K-1).
- 在优化的Pb0.98Bi0.02Se样本中,获得了超过1.5的优点.
结论:
- 已识别的Seebeck系数范围为优化热电性能提供了直观的指标.
- 微结构工程 (移位,孔隙) 和组合调整 (Bi替代) 是增强热电材料的有效策略.
- 该研究表明通过有针对性的优化实现高性能热电材料的途径.
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