在BiCuSeO系统中实现了高热电性能,通过3D调制兴奋剂改善载体流动性
Yan-Ling Pei1, Haijun Wu, Di Wu
1School of Materials Science and Engineering, Beihang University , Beijing 100191, China.
Journal of the American Chemical Society
|September 20, 2014
概括
研究人员通过使用调制兴奋剂来提高载体的移动性来提高BiCuSeO材料的热电性能. 这一策略显著提高了优点 (ZT) 的数字,达到大约1.4.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 能源转换 能源转换
背景情况:
- 热电材料将热量转化为电力.
- 铜氧化物 (BiCuSeO) 显示出热电应用的潜力.
- 提高载体移动性是提高热电性能的关键.
研究的目的:
- 为了提高BiCuSeO系统的热电性能.
- 研究调制兴奋剂对载体运输和热电性质的影响.
- 在BiCuSeO.中取得高功绩 (ZT).
主要方法:
- 制造模块化合的BiCuSeO异构结构.
- 载体运输特性的表征,包括移动性和集中性.
- 测量电导率,西贝克系数和热导率.
- 计算热电功率 (ZT) 的计算.
主要成果:
- 调节兴奋剂增加了2倍的载体运动,同时保持了类似的载体度.
- 实现了高功率系数,范围从5到10μWcm(-1) K(-2).
- 在923K时获得了极低的热导率~0.25W m(-1) K(-1) 在923K时.
- 达到约1.4的热电功率 (ZT) 的峰值.
结论:
- 调制兴奋剂是一种有效的策略,可以提高BiCuSeO的热电性能.
- 功率因子和低导热率的协同改进导致高的ZT值.
- 这项工作证明了BiCuSeO在高效的热电能转换方面的潜力.
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