中文摘要：

采用水热合成法结合放电等离子烧结技术制备了Ag2S/Bi2S3块体热电复合材料。采用XRD、SEM和TEM对合成粉末材料的相组成和微观形貌进行分析,闪光法和塞贝克系数/电阻测量系统测试复合块材的热电性能,系统地研究了Ag2S的含量对Ag2S/Bi2S3复合材料热电性能的影响。实验结果表明,水热法成功地合成了具有球形结构的Ag2S/Bi2S3复合粉末;块体样品的塞贝克系数都为负,说明样品为n型半导体;适量的Ag2S复合Bi2S3不仅有效地降低了材料的热导率,同时也提高了电导率;当Bi2S3与3%的Ag2S复合时样品的热电优值（ZT值）最大,其在724K时的ZT值为0.23,为纯Bi2S3样品在该温度ZT值的2.3倍。

英文摘要：

Ag2 S/Bi2 S3 composite powders with spherical structure was synthesized successfully by hydrothermalmethod and then pressed into bulk by spark plasma sintering technique. The crystalline structure and morpholo-gy of the powder was determined by X-ray diffraction and scanning electron microscopy. The effect of Ag2 S con-tent on the Ag2 S/Bi2 S3 composite thermoelectric properties was investigated systematically. The thermoelectricperformance results showed that the Seebeck coefficients of all the Ag2 S/Bi2 S3 samples were negative, which in-dicated that the composites were n-type semiconductors. Appropriate Ag2 S added in Bi2 S3 could not only reducethe thermal conductivity, but also enhanced the electrical conductivity. The maximal ZT of Bi2 S3 with 3 % Ag2 Swas 0.29 at 724 K, which is twice than that of the pure Bi2S3.