大流动性使N型AgPb18+SbTe20晶体具有更高的热电冷却和发电性能
Yingcai Zhu1, Yuan Yu2, Huaide Zhang2
1School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
Journal of the American Chemical Society
|November 3, 2023
概括
生长Pb补偿的AgPb18+SbTe20晶体显著提高了室温附近的载体移动性和热电性能. 这一突破使得高效的热电冷却和发电应用成为可能.
科学领域:
- 材料科学
- 固态物理
- 热电器
背景情况:
- 在冷却应用中,室温热电性能至关重要.
- 载体的移动性对电子传输特性产生重大影响,特别是在室温附近.
- 通过组合控制和晶体生长可以实现载体流动性的优化.
研究的目的:
- 使用垂直布里奇曼方法生长Pb补偿的AgPb18+SbTe20晶体.
- 研究晶体生长对载体移动性和热电性能的影响.
- 评估这些材料在热电冷却和发电方面的潜力.
主要方法:
- 垂直布里奇曼晶体生长方法
- 载体移动性的测量.
- 热电性质的表征 (功率系数,ZT).
- 热电模块的制造和测试
- 原子探头断层扫描用于微结构分析.
主要成果:
- 在AgPb18.4SbTe20晶体中达到~410 cm2Vs-1的加权移动性,比多晶体同类高~4倍.
- 消除晶体中的粒度边界和富含Ag的位移,通过原子探头断层扫描进行验证.
- 获得了高功率系数~37.8μW cm-1 K-2,在303K时的功率 (ZT) 是~0.6.
- 证明了7对热电模块的冷却温度差 (ΔT) 为42.7K,发电效率为3.7%.
结论:
- 通过增强载体的移动性,晶体生长显著提高了低温热电性能.
- Pb补偿的AgPb18+SbTe20晶体在室温附近显示出有前途的热电应用.
- 优化晶体生长为高效的热电冷却和发电设备提供了途径.
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