Gd 和 Se 双替代四面体的热电特性
Umasankar Rout1, Ramesh Chandra Mallik1
1Thermoelectric Materials and Devices Laboratory, Department of Physics, Indian Institute of Science, Bangalore, 560012, India. rcmallik@iisc.ac.in.
Dalton transactions (Cambridge, England : 2003)
|January 26, 2024
概括
这项研究通过取代加多和来增强环保的四面体热电材料. 优化的材料实现了峰值功率因子和降低了导热率,从而获得了高功率 (zT).
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 热电学是一种热电学.
背景情况:
- 四面体 (Cu12Sb4S13) 是一个环保的p型热电材料.
- 丰富的土壤,低成本和更少的有毒成分使其对能源应用具有吸引力.
- 提高其热电性能对于实际应用至关重要.
研究的目的:
- 为了研究Gd和Se双置换四面体的热电性质.
- 优化组合以提高热电性能.
- 了解Gd和Se替代对结构性和电子性质的影响.
主要方法:
- 固态合成和高真空热压是用来准备样品的.
- 用X射线衍射 (XRD) 和电子探针微分析 (EPMA) 来进行结构特征.
- 拉曼光谱和X射线光电子光谱 (XPS) 用于结合和氧化状态分析.
- 热电特性测量 (功率系数,导热率) 和卡拉威模型分析.
主要成果:
- 由于Se的替代,成功形成了四面体阶段,并增加了网格参数.
- 替代 Gd 降低了载体度,而替代 Se 增强了热力.
- 最大功率系数为~1.35 mW m-1 K-2,最低导热率为~1.18 W m-1 K-1,在729 K的样本x=0.4.4的温度下实现.
- 样本x=0.4表现出一个值 (zT) 的数字为~0.83.3.
结论:
- Gd和Se的共同替代有效地优化了四面体的热电特性.
- 观察到的改善归因于载体度降低和通过共振状态增强的热力.
- 优化的四面体材料显示了热电能转换的巨大潜力.
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