摘要
PbTe是目前唯一商业化应用的温差发电用中温区热电材料。大量研究表明,高压方法能够合成热电材料并有效调制其电声输运性能。目前针对PbTe的高压研究均为n型材料,而热电材料的应用还需要热膨胀系数相近的p型材料。因此,利用高压合成技术快速制备了Te过量的PbTe热电材料,并对其室温下的热电输运性质进行了测试和分析。结果表明,当Te过量6%时,PbTe为空穴导电,属于p型半导体;通过改变Te的含量,能够优化PbTe的电声输运性能,提高其功率因子且降低热导率。高压合成p型PbTe1.12的最大热电优值达到0.21,比相同方法制备的标准化学计量比的PbTe提高了50%。研究结果表明,高压方法结合化学计量比调整能够制备出高热电性能的p型PbTe热电材料。
PbTe is the only thermoelectric material that has been commercially used for power generation in the medium temperature. It has been found that the n-type PbTe with high performance can be synthesized by high pressure method,but so far there has been no report on similarly prepared p-type PbTe ,which is also needed for the application of thermoelectric materials. In this study,we successfully synthesized PbTe with an excess of Te using the high pressure method,and studied their thermoelectric properties at room temperature. It turns out that the main carriers of PbTe with 6% excess Te are holes,indicating that they are p-type semi- conductors. By changing the content of Te, we optimized the electrical transport properties of PbTe and decreased their thermal conductivities. The maximum figure-of-merit, 0.21, was obtained for p-type PbTe 1. n, which is about 50% higher than that of PbTe with standard stoichiometric ratio synthesized by the same method. All the results show that the high pressure method, combined with the adjustment of the stoichiomet- ric ratio,can prepare p-type PbTe thermoelectric materials that possess high thermoelectric performance.
出处
《高压物理学报》
CAS
CSCD
北大核心
2016年第6期448-452,共5页
Chinese Journal of High Pressure Physics
基金
国家自然科学基金(51001042)
上海出入境检验检疫局科研计划项目(HK021-2014)
国家质量监督检验检疫总局科技计划项目(2012IK049)
关键词
高压
热电材料
碲化铅
输运性能
igh pressure
thermoelectric materials
PbTe
transport properties
