由于Kondo-Like效应,空缺填充Heusler的热电性能得到了提高
Jiajun Chen1, Zirui Dong1, Qizhu Li2
1School of Materials Science and Engineering, Shanghai University, Shanghai, 200444, China.
Advanced materials (Deerfield Beach, Fla.)
|June 20, 2024
概括
将磁性引入空隙填充的豪斯勒合金中显著提高了热电性能. 这种新的方法通过通过磁电热合优化材料性能来增强热电功率 (zT).
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 热电能转换热电能转换
背景情况:
- 热电材料将热转化为电力,但效率受到合性质的限制.
- 集成磁性为热电增强提供独特的自旋依赖性质.
- 填空Heusler合金为热电应用提供了可调节的框架.
研究的目的:
- 为了研究内在磁电热合对热电性能的影响.
- 探索磁性 (Cr) 离子在海斯勒合金空缺部位的潜力.
- 为了增强Nb$_{0.75}$Ti$_{0.25}$FeCr$_{x}$Sb合金中的热电功率 (zT).
主要方法:
- 合成Nb$_{0.75}$Ti$_{0.25}$FeCr$_{x}$不同Cr含量 (0 ≤ x ≤ 0.1) 的Sb合金.
- 热电性质的表征,包括Seebeck系数和热导率.
- 分析磁力对电子结构和热传输的影响.
主要成果:
- 在973 K.实现了1.21的显着的热电功率 (zT) 值.
- 由于磁性,观察到Seebeck系数增加和热导率降低.
- 证明了磁力在增加密度状态有效质量和降低电子热导率方面的作用.
结论:
- 内在的磁电热合有效地提高了海斯勒合金的热电性能.
- 引入磁是先进热电材料的一个有前途的战略.
- 通过平衡电子流动性和有效质量的进一步优化,可以获得更高的zT值.
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