隔空和共振水平使n型SnSe多晶体的高热电性能成为可能
Yaru Gong1, Wei Dou1, Bochen Lu2
1National Key Laboratory of Advanced Casting Technologies, MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology, Engineering Research Center of Materials Behavior and Design, Ministry of Education, Nanjing University of Science and Technology, Nanjing, China.
Nature communications
|May 18, 2024
概括
研究人员为热电应用增强了N型多晶锡化物 (SnSe). 通过引入二度容量缺陷和共振水平,他们实现了创纪录的ZT值2.2,超过了以前的限制.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 纳米技术 纳米技术
背景情况:
- 由于其可加工性,N型多晶锡化物 (SnSe) 对热电器件具有前景.
- 目前的研究尚未在n型SnSe.Se中超过2.0的ZT值.
- 提高热电性能需要策略来提高功率 (ZT) 的数字.
研究的目的:
- 为了显著提高n型多晶SnSe.Se的ZT值.
- 探索二空缺缺陷和共振水平对热电性质的协同效应.
- 在n型SnSe中实现超过2.0的ZT记录.
主要方法:
- 在SnSe传导带中引入二度空位缺陷 (Sn和Se空位) 和 (W) 共振水平.
- 利用 tungsten hexachloride (WCl6) 兴奋剂来增加载体度并创造 Se 的空缺.
- 分析微观结构以了解来自缺陷和沉的声子散射机制.
主要成果:
- 在773 K时,在n型SnSe0.92 + 0.03WCl6.6中实现了创纪录的高峰ZT2.2
- 位缺陷和W共振水平的协同效应提高了Seebeck系数.
- 增强的电导率和减少的晶格热导率有助于高功率系数.
结论:
- 缺陷工程和共振水平引入的联合策略有效地提高了SnSe热电性能.
- 通过缺陷和纳米沉的声子散射实现超低的格子导热性至关重要.
- 这项工作为n型多晶SnSe热电材料设定了新的基准.
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