摘要
采用水热法制备平均粒度约300 nm的六方相Bi2Te3纳米粉末。再以Bi2Te3粉末为原料,采用封管熔炼法制备N型(Bi2Te3)0.9(AgxBi2-xSe3)0.1(x为Ag的摩尔分数。x=0.1,0.2,0.3,0.4)合金粉体材料,通过快速热压制备N型(Bi2Te3)0.9(AgxBi2-xSe3)0.1块状热电材料。在300～550 K温度范围内研究该材料的热电性能与Ag掺杂量之间的关系,以及热压工艺对材料热电性能的影响。结果表明在775 K,40 MPa条件下烧结20 min后材料的相对密度达到97%以上,晶粒大小在3μm左右。当Ag掺杂量x=0.2时,在300 K温度下热导率达到最小值0.71 W/mK,同时获得最高的热电优值(ZT值)1.07。
Hexagonal phase Bi2Te3 nanoparticles with average grain sizes of about 300 nm were synthesized by hydrothermal method. And then the Bi2Te3 based N-type（Bi2Te3）0.9（AgxBi2-xSe3）0.1 blocky samples were successively prepared using the nanoparticles via solid-state reaction in vacuum quartz ampoules by a rapid hot-press route. The microstructure and thermoelectric properties of the N-type（Bi2Te3）0.9（AgxBi2-xSe3）0.1 samples were investigated in the temperature range from 300 K to 550 K. The rapid hot-pressing process and influences of the Ag dopant on the thermoelectric properties were also studied. Analysis showed that the relative densities of the samples achieved over 97% of the theoretic densities with the average grain sizes of about 3μm at 775 K for 20 minutes under 40 MPa. The minimum value of thermal conductivity （0.71 W/mK） and the maximum value of ZT 1.07 were obtained at 300 K synchronously, with x value of 0.2.
出处
《粉末冶金材料科学与工程》
EI
2009年第3期157-163,共7页
Materials Science and Engineering of Powder Metallurgy
基金
国家高技术研究发展计划(863计划)资助项目(2007AA03Z301)
国家重点基础研究发展规划(973计划)资助项目(2007CB9-36001)
国家自然科学基金资助项目(2071032)
国家教育部“新世纪优秀人才支持计划”资助项目(NCET-04-0561)
解放军总装备部重点创新项目(7130703)
