采用超声化学法结合还原热处理合成了单相的AgSbTe2粉体, 并结合放电等离子烧结(SPS)制备了相应的块体. 系统研究了不同前驱体制备条件、热处理温度、时间和起始化学计量比对相组成的影响, 并对烧结块体的热电性能进行了初步研究. 结果表明: 超声化学法合成的前驱体在500℃、2h还原热处理后可以得到近单相的AgSbTe2,且通过调节起始原料的摩尔比可以得到单相的AgSbTe2. 所得粉体颗粒平均粒径约为10?m, 表面均匀分布着20~50nm的纳米颗粒. 性能测试表明单相样品的无量纲热电优值ZT值在570K最大可达1.14.
Single-phase AgSbTe2 powder was synthesized by sonochemicial method combining with deoxidizing heat-treatment. The influences of heat-treatment temperature, time and the initial ratio of starting reactants on the phases of the final products were investigated. Near single-phase AgSbTe2 ternary powder can be obtained after 2h heat treatment under 500℃, and single-phase AgSbTe2 can be obtained by changing the initio ratio of the starting reactants. Microstructure analysis shows that nanodots with dimension of 20-50nm are uniformly distributed on the surface of the as-prepared powders with the average size of about 10?m. A dimensionless thermoelectric figure of merit ZT = 1.14 is obtained at 570K for the sample with single phase.
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