温差电致冷原理及赝三元半导体致冷材料的性能

本文从温差电致冷原理出发 ,分析了哈师大物理系研制的大尺寸优质半导体致冷材料的主要温差电性能 .

赝三元GeTe-MnTe-SnTe温差电材料研究

GeTe基温差电材料为性能良好的中温温差电材料。以GeTe为基体,在其中加入MnTe和SnTe形成固熔体合金,研究固熔体比例变化对材料热电性能及机械强度的影响。此外,通过放电实验发现,该材料在工作温度下工作一段时间后发生明显蠕变变形,进而影响其输出电性能。通过在该材料热压粉体中添加高温金属弥散相,在不影响材料热电性能的前提下减小其蠕变变形量。对制备的GeTe基材料进行性能表征,其最大ZT值达到1.57;将该材料在873K、100 N载荷的条件下保持48 h后,其蠕变形变量不超过0.27%。

热塑形方法制备N型Bi_2Te_3材料(英文)

本文介绍了采用热塑形方法制备N型Bi2Te3温差电材料。并且给出了所获得样品的密度、抗弯强度、SEM以及温差电性能(包括电导率和塞贝克系数)的测试结果。实验结果表明,在最佳的热塑形工艺下制备的样品的功率因子与区熔材料相当,但其机械强度要明显优于区熔材料。热压塑形样品在垂直于塑形压力的方向上具有良好的取向,并且样品在此方向上的功率因子远远大于其在平行压力方向上的功率因子值。

A New Technology to Measure the Thermoelectric Performance of Nanowire Array Structure

Recently, the study on one-dimensional thermoelectric materials is getting more and more attention. For those one-dimensional thermoelectric materials with nanowire array structure fabricated with alumina film as template, its thickness is often in the range of 10 to several tens micrometers, and the conventional measurement cannot be used. The key difficulties of the thermoelectric performance measurement for nanowire array materials include two aspects: 1) How to heat the two sides of the specimen uniformly and keep the temperature difference constantly at the same time; 2) How to measure the temperature of the two sides of the specimen with the thickness of 10 to several tens micrometers. A new type heating and temperature measuring technology has been used, and it can be simply described as liquid heating and separate temperature measurement. According to this principle, a thermoelectric performance measurement system has been established.