【摘要】 (In2Te3)x(SnTe)1-x系列化合物具有较低的电导率和热导率,热电性能较差。考虑到其中的In2Te3单元具有三分之一的阳离子空位,可以通过掺杂Cu等外来原子来占据In的空位,使化合物的载流子浓度达到最优化,降低材料的热导率从而改善其热电性能。本组实验中,采用真空熔炼、机械球磨及放电等离子烧结技术制备了(In2-x Cux Te3)0.08(SnTe)0.92(x=0.025,0.05,0.2)系列化合物。测试结果表明,掺杂不同摩尔数的Cu元素后,材料的Seebeck系数几乎没有变化,电导率有所提高,晶格热导率L值大幅度降低,成功地抑制了高温区(In2Te3)0.08(SnTe)0.92的双极扩散效应。当x=0.2时,该化合物在647 K取得最大ZT值0.29,是掺杂Cu元素前ZT值的4.6倍。更多还原

【Abstract】 (In2 Te3)x(SnTe)1-x compounds usually have low electrical conductivity and thermal conductivity,whose thermoelectric(TE) property was expected to be improved through Cu elemental doping since only two thirds of the cation sites are occupied in In2 Te3.In the present work In element was substituted for Cu in the(In2 Te3)0.08(SnTe)0.92 compound with the same molar fraction and(In2-x Cux Te3)0.08(SnTe)0.92(x = 0.025,0.05,0.2) compounds were prepared by "Melting-Ball Milling-Spark Plasma Sintering".Measurements reveal that although the Seebeck coefficient of the sample is almost unchanged,the electrical conductivity increases slightly and lattice thermal conductivity significantly decreases after Cu doping.The highest ZT value of 0.29 is obtained at 647 K when x=0.2,enhanced by about 3.6 times of the Cu-free(In2 Te3)0.08(SnTe)0.92 compound at the corresponding temperature.更多还原