对RE2(Fe,Co)14B (RE=稀土) 化合物的横向热电转换进行系统的研究
Babu Madavali1, Fuyuki Ando1, Takamasa Hirai1
1Research Center for Magnetic and Spintronic Materials, National Institute for Materials Science, Tsukuba, Japan.
Science and technology of advanced materials
|July 16, 2025
概括
这项研究探讨了用于横向热电发电的稀土基化合物,发现Tb2Fe14B表现出强烈的负反常Nernst效应. 在Nd2(Fe,Co) 14B合金中替代可以逆转这种效应,从而实现高效的废热转换.
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
- 热电学是一种热电学.
背景情况:
- 利用异常的Nernst效应 (ANE) 的横向热电发电 (TEG) 为废热回收提供了一个有前途的途径.
- 像Nd2Fe14B这样的永久磁铁使TEG设备无需外部磁场,但缺乏对稀土 (RE) 化合物的系统研究.
研究的目的:
- 在室温下系统地研究RE2Fe14B和Nd2(Fe,Co) 14B化合物的横向热电特性.
- 了解稀土元素和替代对异常纳斯特效应的影响.
主要方法:
- 合成和表征RE2Fe14B (RE = Tb,Dy,Ho,Nd) 和Nd2 ((Fe1-pCop) 14B合金.
- 在室温下测量横向热电性质,特别是异常Nernst系数 (S_ANE).
主要成果:
- 所有研究的RE2Fe14B合金都表现出负的S_ANE,其中Tb2Fe14B显示出最高值 (-0.67 × 10^-6 VK^-1).
- 在Nd2(Fe,Co) 14B合金中的替代导致S_ANE的标志从负转为正.
- 2 ((Fe0.4Co0.6) 14B合金表现出最高的阳性S_ANE (1.87 × 10^-6VK^-1),表明了RE和3d过渡金属的不同作用.
结论:
- 稀土元素和3D过渡金属显著影响RE2 ((Fe,Co) 14B化合物的横向热电性能.
- 这些发现为设计高效横向热电能收集的先进材料提供了基础.
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