点缺陷散射和声波软化,以实现p型 ZnSb的高热电性能,具有最佳载体度
Dongyi Shen1, Siu Ting Tai1, Kejia Liu1
1Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR , China.
ACS applied materials & interfaces
|March 10, 2025
概括
兴奋剂和合金显著提高了抗敏化物 (ZnSb) 的热电性能. 这项研究提高了热电功率 (zT) 的数字,用于实际应用.
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 有机化学
背景情况:
- Antimonide (ZnSb) 是一个有前途的热电材料,因为它的稳定性和地球上丰富的元素.
- 其实际使用受到低功率因子和高晶格导热率的阻碍.
研究的目的:
- 为了提高 ZnSb. 的热电功率 (zT) 值.
- 研究 (Ge) 兴奋剂和 (Cd) 合金对ZnSb热电特性的影响.
主要方法:
- 在Sb位点进行GE兴奋剂,以优化载体度.
- 在Zn位点合Cd以诱导声子散射和软化声学声子.
- 热电性质的实验性表征.
主要成果:
- 达到82%的峰值功率因子的增加,达到0.6%的Gedoping.
- 在 Zn0.7Cd0.3Sb.中观察到网格导热率降低了44%.
- 在Zn0.7Cd0.3Sb0.96Ge0.04中,在564 K时达到大约1.08的zT峰值.
结论:
- 结合的Ge和Cd合金有效地提高了ZnSb的热电性能.
- 优化的材料显示出大规模热电装置应用的潜力.
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