中文摘要：

采用水热法制备PbS粉末,然后通过放电等离子烧结（SPS）和冷压两种不同的工艺制备PbS块体.采用XRD、TEM和SEM对材料的相组成和微观结构进行分析,并使用激光导热仪和塞贝克系数/电阻测量系统对材料的热电性能进行测试.实验结果表明,在150℃和180℃水热合成的PbS粉末的形貌主要为树枝状和星形,晶粒具有分级的纳米结构,在180℃合成的PbS粉末具有更多的星形结构;采用SPS的样品因晶粒尺寸没有发生明显的增大,并且致密度较高,表现出较高的电导率以及较低的热导率,从而具有相对而言较为优异的热电性能.SPS样品的最大ZT值为0.29,比冷压样品高81％.

英文摘要：

PbS powders were synthesized by hydrothermal method,and the powders were consolidated into bulk ceramic by spark plasma sintering （SPS） and cold pressing,respectively.XRD,TEM and SEM were used to identify the crystalline structure and morphology.The Seebeck coefficient and electrical resistivity were measured by a Seebeck coefficient/electric resistance measuring system,the thermal diffusivity was measured by the laser flash method.The results show that the morphology of the PbS synthesized at both temperatures are mostly dendritic and star-shaped,with hierarchical nanostructures,and there are more star-shaped structures in sample synthesized at 180 ℃.SPS sample represents a higher electrical conductivity and a lower thermal conductivity as SPS process preserving the grain size without notable growth and compact structure,thus improved the thermoelectric property.The highest ZT value of SPS sample is 0.29,which is 81％ higher than the cold-pressed sample.