Thermoelectric Properties of Tl-X-Te (X=Pb, Sn, Ge) Systems

摘要

Polycrystalline-sintered samples of Tl_2GeTe_3, Tl_4SnTe_3, and Tl_4PbTe_3 were prepared by a solid-state reaction. Their thermoelectric properties were evaluated at temperatures ranging from room temperature to ca. 700 K by using the measured electrical resistivity (ρ), Seebeck coefficient (S), and thermal conductivity (κ). Despite their poor electrical properties, the dimensionless figure of merit ZT of all the compounds was relatively high, i.e., 0.74 at 673 K for Tl_4SnTe_3, 0.71 at 673 K for Tl_4PbTe_3, 0.29 at 473 K for Tl_2GeTe_3, due to the very low lattice thermal conductivity of the compounds.