Composition-Dependent Thermoelectric Properties of PbTe Doped with Sb₂Te₃

Abstract

Although there are many reports on PbTe–SnTe and Bi₂Te₃–Sb₂Te₃ systems with improved thermoelectric performance due to reduced lattice thermal conductivity, only few experimental data exist on PbTe–Sb₂Te₃ system. In this report, the composition-dependent thermoelectric properties of PbTe doped with Sb₂Te₃ have been studied at room-temperature. It is worth noting that the lattice thermal conductivity is only about 1 W/K·m as the contents of Sb₂Te₃ is larger than 0.8 mol%. In addition, the figure of merit shows a maximum value of 1.03×10⁻³ K⁻¹ with the content of Sb₂Te₃ at 0.8 mol% which is the highest value obtained in doped bulk PbTe samples and is several times higher than that of PbTe containing other dopants with small grain sizes. This confirms that Sb₂Te₃ is one of the best dopants for PbTe to enhance its thermoelectric performance.