通过调节Bi-Te比率启用高性能p型Bi2Te3基热电材料
Xiaolei Wang1,2, Hongjing Shang2,3, Hongwei Gu2,3
1College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
ACS applied materials & interfaces
|February 22, 2024
概括
高性能木化 (Bi2Te3) 合金被开发用于热电应用. 新材料具有出色的热电和机械性能,为更广泛的工业应用铺平了道路.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 纳米技术纳米技术
背景情况:
- 基于比斯穆特化物 (Bi2Te3) 的合金是商业上唯一可用的热电材料.
- 现有的Bi2Te3合金的热电效率低,机械性能差,成本高,阻碍大规模应用.
- 需要先进的热电材料,以提高性能和耐用性.
研究的目的:
- 开发基于p型Bi2Te3的高性能热电材料.
- 为了提高热电效率和机械性能,用于实际应用.
- 研究改善载体和声传输的处理方法.
主要方法:
- 使用球磨和热压技术制备p型Bi2Te3基材料.
- 优化合金的组成,特别是Bi0.55Sb1.45Te3 + 2.5 wt % Bi.
- 热电性质 (功率图,zT) 和机械性质 (维克尔硬度,压力强度) 的表征.
主要成果:
- 优化的p型Bi0.55Sb1.45Te3 + 2.5 wt % Bi在360 K时达到1.45的高峰热电功率 (zT).
- 在300-480K的温度范围内记录了1.24的平均zT值,相当于最先进的Bi2Te3合金.
- 观察到显著改善的机械性能,维克尔硬度达到0.95 GPa,压力强度高达94.6 MPa.
- 增强的电导率和减少的晶格热导率归因于优化的载体和声子传输.
结论:
- 球磨和热压方法成功生产了基于Bi2Te3的材料,具有具有竞争力的热电和机械性能.
- 取得的性能证明了甲化合金在工业应用方面的潜力.
- 这项工作为专注于改进热电设备的基于Bi2Te3材料的研究人员提供了宝贵的见解.
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