在基于TiCoSb的单晶半Heuslers中,优越的电子传输
Sheng Ye1, Shizhen Zhi1, Xiaojing Ma1
1School of Materials Science and Engineering, and Institute of Materials Genome & Big Data, Harbin Institute of Technology (Shenzhen), Shenzhen, P.R. China.
Nature communications
|February 24, 2025
概括
高质量的TiCoSb单晶实现了超过1.0 zT的高效热电发电. 热电材料的这一突破为将热量转化为电力提供了一个有前途的途径,其性能得到了提高.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 能源转换 能源转换
背景情况:
- 半斯勒材料对中高温热电发电具有前景.
- 多晶半Heusler由于缺陷主导的电子散射而表现出有限的电子特性.
研究的目的:
- 合成高质量的基于TiCoSb的单晶,以提高热电性能.
- 调查兴奋剂和合金对TiCoSb.热电特性的影响.
主要方法:
- 合成大尺寸 (大于1厘米) 的基于TiCoSb的单晶体.
- 与Nb/Ta一起配合,并与Hf合金,以优化热电特性.
- 在广泛的温度范围内评估电子和热传输特性 (307973 K).
主要成果:
- 在n型单晶Ti1-x中实现了~37μW cm-1 K-2的平均功率因子.由于电子移动性得到改善,NbxCoSb在n型单晶Ti1-x中实现了~37μW cm-1 K-2的平均功率因子.
- 通过增强散射机制,Hf合金有效地抑制了晶格导热性.
- 实现了1.0以上的高峰热电功率 (zT),超过了以前的多晶材料.
- 在700K的温度差异下,单个腿的热电转换效率达10.2%.
结论:
- 基于TiCoSb的单晶显示出对先进的热电发电具有重大前景.
- 这些发现为探索其他单晶半Heusler用于改进热电器件提供了途径.
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