高性能散装热电器电子频段的融合
Yanzhong Pei1, Xiaoya Shi, Aaron LaLonde
1Materials Science, California Institute of Technology, Pasadena, California 91125, USA.
Nature
|May 6, 2011
概括
研究人员通过增加散装合金中的谷变性来增强热电材料的废热回收. 这一突破实现了1.8的高功率 (zT),为高效的热电转换铺平了道路.
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:
- 热电发电机直接将热量转化为电力,并用于废热回收.
- 目前的热电材料的效率有限 (优点数字,zT <1.5),阻碍了广泛采用.
- 众所周知,电子频段的高谷退化可以提高热电效率.
研究的目的:
- 开发新的热电材料,其功率 (zT) 值在1.5以上,用于实际应用.
- 研究增加散装热电材料中的谷退化的方法.
- 展示改善散装热电材料的总体策略.
主要方法:
- 大量PbTe{1-x) Se{x) 合金中的工程带结构,通过调和组合.
- 实现了电子带谷的融合.
- 在高温下测量热电特性.
主要成果:
- 在化PbTe{1-x) Se{-x) 合金中证明了至少12个电子谷的融合.
- 在大约850克尔文时达到1.8的非凡热电功率 (zT).
- 展示了Seebeck系数和电导率的同时改进.
结论:
- 波段工程用于汇聚价值或导电波段是增强散装热电材料的可行策略.
- 实现的高谷退化和zT值代表了热电材料的重大进步.
- 这种方法为发现和改进用于高效热电转换的材料提供了通用的途径.
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