高压烧结法制备Bi_2Te_3纳米晶块体热电性能的研究  

Thermoelectric properties of the Bi_2Te_3 nanocrystalline bulk alloy pressed by the high-pressure sintering

作　　者：吴芳[1,3] 王伟[2] 

机构地区：[1]河南教育学院物理与电子工程学院,郑州450046 [2]中州大学信息工程学院,郑州450044 [3]郑州大学物理工程学院,材料物理教育部重点实验室,郑州450052

出　　处：《物理学报》2015年第4期309-314,共6页Acta Physica Sinica

基　　金：河南省重点科技攻关项目(批准号:142102210043);河南省教育厅科学技术研究重点项目(批准号:14A140017)资助的课题~~

摘　　要：用高压烧结法对水热法制备的Bi2Te3纳米线及纳米颗粒粉体进行了压制成型,并与真空热压法制备的样品进行了形貌和热电性能的比较.研究表明,高压烧结样品内的晶粒尺寸明显小于热压样品.热电性能的研究表明,高压烧结样品的电阻率、赛贝克系数和热导率均优于真空热压样品.由纳米线粉体高压烧结的样品其热电优值ZT在室温时达到了0.5,高于真空热压样品的值,表明高压烧结是热电材料纳米粉体成型的一种有效方法.Bi2Te3 nanowires and nanoparticles are synthesized by hydrothermal method, and the nanopowders are pressed into bulk pellets by high-pressure sintering or vacuum hot-pressed. The scanning electron microscope （SEM） results and thermal properties of such bulk samples are compared. The SEM result shows that the grain size of the high-pressure sintering sample is much smaller than that of the hot-pressed sample. The thermal properties show that the electrical resistivity, Seebeck coefficient, and thermal conductivity of the high-pressure sintering sample are all better than those of the hot-pressed sample. The ZT value of the high-pressure sintering sample prepared by nanowires reaches 0.5 at room temperature, which is much higher than that of the hot-pressed sample. Therefore the high-pressure sintering provides an effective method to press nanopowders to bulk.

关 键 词：热电性能 纳米粉体成型 高压烧结 

分 类 号：TQ135.32[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程]