磁性单元的有序架构触发了厚膜的优异电热转换性能
Haojun Zhang1, Xiaolei Nie1, Shaoqiu Ke1
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
ACS applied materials & interfaces
|May 22, 2025
概括
带有图案的磁纳米粒子的柔性热电薄膜显著提高了电传输和热电转换效率. 在Bi$_{0.5}$Sb$_{1.5}$Te$_{3}$膜中的罗姆形磁单元提高了36.5%的功率因子,提高了冷却性能.
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
- 纳米技术纳米技术
背景情况:
- 灵活的热电 (TE) 薄膜在电传输性能方面存在局限性,通过佩尔蒂埃效应阻碍了飞机内散热.
- 在TE材料中构建磁性单元是提高热电转换效率的有希望的策略.
研究的目的:
- 研究铁磁Fe纳米粒子 (Fe-NPs) 的建筑形状对Bi$_{0.5}$Sb$_{1.5}$Te$_{3}$ (BST) /Fe/BST热电磁 (TEM) 薄膜的微观结构和电热传输特性的影响.
- 为了优化载体运输,并通过控制磁单元排列来减少散射.
主要方法:
- 使用印和热压固化制造TEM薄膜,在BST/环氧层之间使用Fe-NP的有序架构.
- 微观结构和电热传输性能的表征,包括磁阻测试.
主要成果:
- 铁磁单元的有序架构优化了载体路径,减少了散射,提高了电导率 (σ).
- 铁磁单元通过磁性散射和旋转贡献保持了高的西贝克系数 (α).
- 带有体Fe-NP图案 (BST-RhoFe-BST) 的TEM薄膜显示,由于显著的负磁阻,最大功率因子 (PF) 增加了36.5%.
- 使用BST-RhoFe-BST薄膜的单脚设备实现了1.8K的冷却温度差异,比BST-BST薄膜提高了125%.
- 级联装置显示2.8K的温度下降,显示出出色的飞机内散热.
结论:
- 磁性单元的有序建筑形状有效调节TE膜的电热转换性能.
- 磁电阻理论为TEM片中的电荷载体散射机制提供了洞察力.
- 这种方法为开发高级散热应用的高性能灵活热电器件提供了一条途径.
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