| Summary: | Thermoelectric materials can directly convert heat and electricity, which is a kind of promising energy material. In view of cost and mechanical properties, polycrystalline SnSe material with high <i>zT</i> value is greatly desired. In this study, polycrystalline Sn<sub>0.94</sub>Pb<sub>0.01</sub>Se<sub>1-<i>x</i></sub>Te<i><sub>x</sub></i> samples were prepared by the vacuum melting–hot pressing sintering method. Sn vacancies, Pb and Te atoms were simultaneously introduced into the polycrystalline SnSe. The power factor of Sn<sub>0.94</sub>Pb<sub>0.01</sub>Se<sub>1-<i>x</i></sub>Te<i><sub>x</sub></i> samples was decreased, which could be attributed to the generation of <i>n</i>-type semiconductor SnSe<sub>2</sub>. In addition, the phonons were strongly scattered by point defects and dislocations, which led to the decrease of thermal conductivity—from 0.43 Wm<sup>−1</sup>K<sup>−1</sup> to 0.29 Wm<sup>−1</sup>K<sup>−1</sup> at 750 K. Finally, the polycrystalline Sn<sub>0.94</sub>Pb<sub>0.01</sub>Se<sub>0.96</sub>Te<sub>0.04</sub> sample achieved the maximum <i>zT</i> value of 0.60 at 750 K.
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