在SnTe中强合金的价值带修改和高热电性能
Gangjian Tan1, Fengyuan Shi2, Shiqiang Hao2
1Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|August 27, 2015
概括
我们通过与化 (MnTe) 合金实现了高热电性能. 这种补充增强了Seebeck系数并降低了导热率,提高了材料的能量转换效率.
科学领域:
- 材料科学
- 凝聚物质物理学
- 纳米技术
背景情况:
- 锡化物 (SnTe) 是一个有前途的热电材料,但需要优化以提高性能.
- 由于溶解度极低,用 (Cd) 和 (Hg) 等元素合SnTe的成功率有限.
研究的目的:
- 研究化 (SnTe) 与化 (MnTe) 的合金对其热电性能的影响.
- 探索高 Telluride (MnTe) 兴奋剂的潜力,以提高热电性能.
主要方法:
- 将SnTe与MnTe合金,以达到超过9%的可溶性极限.
- 在不同温度范围内测量电导率,西贝克系数和霍尔效应.
- 使用基于密度函数理论 (DFT) 的第一原理电子结构计算.
主要成果:
- 在SnTe中达到MnTe的高可溶性极限>9mol%.
- 随着MnTe含量的增加,观察到Seebeck系数和功率因子的显著增加.
- 由于高Mn注,证明了价值带之间的收,导致Seebeck系数在900K时为230μV/K.
- 由于增强的声子散射,报告了0.9W m-1K-1的低晶格热导率.
- 在900K时达到1.3的高热电功率 (ZT).
结论:
- 在SnTe中高MnTe合有效地改变了电子带结构并增强了热电性质.
- 对电子和声子传输的协同作用导致了优越的热电性能.
- 这项研究为优化基于SnTe的热电技术提供了一个可行的策略.
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