Structural, electronic and thermoelectric properties of PbTe-based chalcogenide compounds

Lead telluride (PbTe) and other lead-chalcogenides such as PbSe and PbS have been extensively investigated due to their potential applications in thermoelectric (TE) devices. Researchers previously reported good values of the figure-of-merit (zT) > 1.7 for PbTe – CdTe alloy at 775 K ¹, and about 1.5 for doped PbTe with Thalium at 773 K ². In addition, experiments showed that doping PbTe with Sn increases the figure of merit to 0.8 at 700 K ³. These promising experimental results were the motivation to carry out the electronic structure calculations of Pb_1-xSn_xTe (x = 0.25, 0.5, 0.75) compounds using density functional theory ⁴ in this study. Based on the semi-classical Boltzmann theorem ⁵, the TE properties are computed and the results will be presented.

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