在RE2SbO2化合物中通过局部结构扰动脱电导率和Seebeck系数
Peng L Wang1, Taras Kolodiazhnyi, Jinlei Yao
1Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1.
Journal of the American Chemical Society
|January 13, 2012
概括
改变稀土抗氧化物 (RE(2) SbO(2) 的晶体结构可以提高热电性能. 这种方法可以提高电导率和Seebeck系数,而不会改变电荷载体度.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 无机化学 无机化学
背景情况:
- 热电研究中的化学兴奋剂面临着由于电导率和Seebeck系数之间的权衡所造成的局限性.
- 优化热电材料需要超越传统兴奋剂方法的替代策略.
研究的目的:
- 探索控制局部晶体结构的潜力,以提高RE(2) SbO(2) 系统中的热电性能.
- 研究稀土元素变化,晶体结构和由此产生的运输特性之间的关系.
主要方法:
- 合成的RE(2) SbO(2) 阶段 (RE = La, Nd, Sm, Gd, Ho, Er) 与一个无序的反-ThCr(2) Si(2) 类型的结构 (I4/mmm).
- 稀土元素的系统变化,以诱导化学压力和扰乱反 (Sb) 位移.
- 分析电荷载体激活机制及其对电导率和Seebeck系数的影响.
主要成果:
- 稀土系列的晶格参数逐渐减少,导致Sb环境上的化学压力增加.
- 对Sb位移的干扰导致了电荷载体激活机制的改变.
- 观察到电导率和Seebeck系数的同时改善,电荷载体度是恒定的.
结论:
- 控制局部晶体结构为增强热电材料提供了替代化学兴奋剂的可行替代方案.
- 该RE(2) SbO(2) 系统通过稀土元素替代证明了可调节的热电特性.
- 这项研究突出了通过操纵晶体结构来设计高效的热电材料的新途径.
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