在p型 (PbTe) 的高ZT1-2x(PbSe) x(PbS) x热电材料
Rachel J Korkosz1, Thomas C Chasapis, Shih-han Lo
1Department of Chemistry, and ‡Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|February 19, 2014
概括
这项研究引入了一种新型的焦化物热电材料 (PbTe) 1-2x(PbSe) x(PbS) x,在800 K时达到约2.0的功率 (ZT).该材料通过波段结构修改和降低导热性来证明增强的热电性能.
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:
- 石化热电器通过带结构修改或纳米结构实现高性能.
- 之前对 (PbTe) 1-x ((PbSe) x和 (PbTe) 1-x ((PbS) x的研究表明,分别具有高功率因子和低导热率.
研究的目的:
- 为了研究 2% Na-doped (PbTe) 1-2x(PbSe) x(PbS) x 系统的伪三极性热电特性.
- 在这个系统中探索固体溶液行为和相位分离之间的相位竞争.
- 为了确定这个系统是否与二进制对应器相比提供了优越的热电性能.
主要方法:
- 合成和特征的伪二次性2%的Na-doped (PbTe)1-2x(PbSe) x(PbS) x系统.
- 测量热电特性,包括功率系数和热导率.
- 对带结构修改和散射机制的分析.
主要成果:
- 2%的Na-doped (PbTe)1-2x(PbSe)x(PbS)x系统在800K时获得了大约2.0的优点 (ZT) 数字.
- 与2%的Na-doped PbTe-PbSe和PbTe-PbS二进制系统相比,观察到优越的热电特性.
- 电导率和热功率在600-800K之间的平原导致功率系数为27μW/cmK.
- 低晶格导热率 (1.1 W/m·K对于x=0.07) 是由于固溶液缺陷引起的声子散射而产生的.
结论:
- 伪三极体 (PbTe)1-2x(PbSe)x(PbS)x系统是高性能热电应用的一个有前途的材料.
- 波段结构的修改和有效的声子散射有助于增强热电功率.
- 材料的性能是由内在特性驱动的,而不是纳米结构.
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