通过协同带工程和纳米结构方法,通过p型SnTe的高热电性能
Gangjian Tan1, Li-Dong Zhao, Fengyuan Shi
1Department of Chemistry and ‡Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|May 3, 2014
概括
锡化物 (SnTe) 是一个有前途的热电材料. 通过应用Sn自我补偿和Cd合金,研究人员提高了其热电性能,达到约1.3.3的功率 (ZT) 值.
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:
- 锡化物 (SnTe) 是用于热电应用的化物 (PbTe) 的无替代品.
- 然而,SnTe的热电性能差是由于Sn空隙的高孔度和高电热导电性.
研究的目的:
- 克服SnTe的局限性,并将其发展为用于发电的高效热电材料.
- 研究Sn自补偿,Cd合金和纳米级沉物对SnTe热电特性的影响.
主要方法:
- 使用Sn自我补偿来减少Sn空位和孔载体密度.
- (Cd) 合金用于设计电子带结构,增强了Seebeck系数和带间隙.
- 引入了内毒CdS或ZnS纳米级沉物,以减少晶格导热率.
主要成果:
- 3mol% Sn的自我补偿使得功绩 (ZT) 的数字提高了50%.
- 在SnCd中合Cd{0.03) Te增强了Seebeck系数,导致ZT值在823K时为~0.96.
- 使用CdS和ZnS沉物的纳米结构产生了最大的ZT值,分别在873K时为~1.3和~1.1 .
结论:
- 基于SnTe的材料可以通过战略性材料设计优化为优良的热电材料.
- Sn自我补偿,Cd合金和纳米结构的组合为高温热电发电提供了一个可行的途径.
- 这些发现将基于SnTe的材料定位为p型石化的潜在替代品.
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