研究Cote2-CoSe2固溶液合金的相位形成和热电传输特性
Seungchan Seon1, BeomSoo Kim1, Changwoo Lee1
1Department of Materials Science and Engineering, University of Seoul, Seoul 02504, South Korea.
The Journal of chemical physics
|February 3, 2025
概括
这项研究合成了用于热电应用的Co(Te1-xSex) 2合金. 虽然热导率随着的增加而下降,但功率因子和zT值是有限的,尽管立方CoSe2显示出了希望.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 热电材料 热电材料
背景情况:
- 由于其电气性质, telluride (CoTe2) 和 selenide (CoSe2) 合金对热电应用具有前景.
- 固体解决方案通过修改材料组成来调整热电性能.
- 了解相位形成和传输特性对于优化热电器件至关重要.
研究的目的:
- 为了研究CoTe2-CoSe2固体溶液的相位形成和热电传输特性.
- 探索不同含量 (x) 对结构和热电特性的影响.
- 识别具有增强热电功率 (zT) 的组合物.
主要方法:
- 一系列Co(Te1-xSex) 2组合物的合成 (x = 0, 0.25, 0.50, 0.75, 1.0).
- 使用X射线衍射进行相位分析.
- 测量热电传输特性,包括功率系数,霍尔运动性和导热性.
主要成果:
- 对于x ≤0.50观察到的正合体CoTe2阶段;对于x = 0.75.5的正合体CoTe2和立方体CoSe2的共存.
- 功率因子和霍尔的移动性下降到x=0.50.
- 总导热率随着x的增加而下降到0.50. 立方CoSe2在700K时显示了0.13的最高zT.
结论:
- CoTe2-CoSe2固体溶液表现出复杂的相位行为和不同的热电特性.
- 虽然热导率随着的增加而下降,但功率因子的限制阻碍了某些组成中的zT增强.
- 建议减少载体度作为一个关键策略,以显著提高整个系列的功率因子和zT.
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