缺陷能量准格子修复在抗中提供了高热电性能
Jiahao Jiang1, Minhui Yuan1,2, Yuntian Fu3
1School of Materials, Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China.
Journal of the American Chemical Society
|March 14, 2026
概括
我们通过用土金属取代的空缺来增强基于的热电. 这一战略促进了载体的移动性和降低了导热率,实现了高效废热回收的创纪录的优点.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 热电学是一种热电学.
背景情况:
- 基于的Mg3(Sb,Bi) 2对废热回收具有前景.
- 内在的Mg空缺限制了散射载体的热电性能.
研究的目的:
- 通过修复Mg的空缺来克服Mg3的性能限制.
- 通过以缺陷能量为目标的格子修复策略来增强热电特性.
主要方法:
- 用同类土金属 (Ca,Sr,Ba) 替换了不稳定的Mg位点.
- 利用理论计算来分析缺陷能量和结合.
- 研究了兴奋剂对载体运输和导热性的影响.
主要成果:
- 空位形成能量从~0.97增加到~2.42 eV,抑制了空位的产生.
- 在不影响载体度的情况下,实现了~35%的载体移动性增加.
- 在773 K. 降低格子导热率到~0.4 W m-1 K-1.
- 在773K达到~2.1的峰值值值 (zT) 和~1.5的平均zT.
结论:
- 针对缺陷能量是一个强大的方法来改进Zintl相热电.
- 开发的战略显著提高了热电性能,使废热回收有效.
- 在单脚设备中显示了~14%的记录转换效率.
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