实现BiCuSeO氧化物的热电性质的简单优化,通过自我替代诱导的格子位移
Rui Xu1,2, Zhiwei Chen3, Qizhu Li1
1Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology and School of Materials Science and Engineering, Anhui University, Hefei 230601, China.
Research (Washington, D.C.)
|June 8, 2023
概括
这项研究引入了一种新的方法,通过自我兴奋剂在BiCuSeO氧化物中产生排位,显著提高热电性能. 这种简单的优化策略实现了1.32的高功率 (zT),为高效的热电材料铺平了道路.
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:
- 优化热电性能与最小的兴奋剂对可持续材料开发至关重要.
- 在刚性氧化物系统中引入脱位缺陷是具有挑战性的,因为应变能量的限制.
研究的目的:
- 通过自我兴奋剂在BiCuSeO中成功构建密集格子脱位.
- 为了实现热电性质的简单优化,使用最小的外部兴奋剂.
- 研究失位对声子散射和热电性能的影响.
主要方法:
- 在BiCuSeO的O位点 (SeO自我替代) 进行Se的自我兴奋.
- 有限的外部Pb兴奋剂用于构成平面化和属性增强.
- 对失位密度,格子导热率,电导率和Seebeck系数的分析.
主要成果:
- 在BiCuSeO颗粒中成功形成了高密度位移 (3.0 × 10^14 m^-2).
- 在823K时,格子导热率大幅降低至0.38W m^-1 K^-1 .
- 在823 K的峰值功率系数达到942 μW m^-2 K^-2,最高的zT值为1.32.
结论:
- 自我兴奋剂和最小的Pb兴奋剂有效地产生了位移,增强了BiCuSeO的热电特性.
- 开发的战略为热电材料的简单优化提供了一条途径.
- 脱位工程方法为设计其他氧化物系统中的脱位提供了灵感.
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