Cu2SnSe3是一种不含稀贵或有毒元素的新型热电材料,具有较低的热导率和较高的电导率,通过掺杂可大大提高Cu2SnSe3的热电优值,使其有望在中温区附近得到应用.通过燃烧合成直接一步制备出致密的Cu2SnSe3块体材料,其相对密度在96％以上,最大热电优值为0.48,与传统烧结工艺制备的样品性能相当,整个反应过程在数分钟内即迅速完成,从而极大的简化了合成工艺.为进一步提高Cu2SnSe3材料的热电性能,本文利用燃烧合成方法制备多晶块体材料,采用S、Te两种元素对Cu2SnSe3进行掺杂,系统研究了掺杂对热电性能的影响.结果表明,S、Te两种元素的Se位掺杂提高了Seebeck系数,降低了热导率和电导率,最终使热电优值有所提升.S掺杂Cu2SnSxSe3-x样品中,当x=0.15时在温度773 K下取得最大ZT值为0.66.Te掺杂Cu2SnTexSe3-x样品中,当x=0.05时在温度773 K下取得最大ZT值为0.40.%Cu2SnSe3 is a kind of new thermoelectric material with low or no poisonous elements. It has low thermal conductivity and high conductivity. The doping of Cu2SnSe3 can greatly improve the thermoelectricity of Cu2SnSe3, which is expected to be applied near the middle temperature region. The relative density of Cu2SnSe3 bulk material prepared by direct combustion synthesis is over 96％, and the maximum thermoelectricity is 0.48. It is equivalent to the sample prepared by the traditional sintering process. The whole reaction process is completed in a few minutes, thus greatly simplifying the synthesis process. In order to further improve the thermoelectric properties of Cu2SnSe3 materials, the polycrystalline bulk materials were prepared by combustion synthesis method. The effects of doping on the thermoelectric properties were investigated by doping Cu2SnSe3 with S and Te. The results show that the Se doping of S and Te increases the Seebeck coefficient, decreases the thermal conductivity and electrical conductivity, and improves the thermoelectricity value. S doped Cu2SnSxSe3-x samples, when x=0.15 at 773 K temperature to obtain the maximum ZT value of 0.66. Te-doped Cu2SnTexSe3-x samples, the maximum ZT value was 0.40 at a temperature of 773 K at x = 0.05.
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