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The phase composition and thermoelectric properties of solid solutions Pb16Sn2Ag2Te20 and Pb14Sn4Ag2Te20 are researched. Biphasic structure of the samples is installed, which providing to low values of thermal conductivity. Best samples have values of dimensionless thermoelectric figure of merit ZT ≈ 0,55.

The results of study of thermoelectric properties of lead telluride obtained by method of powder pressing arepresented. A modified electrical model for interpreting the empirical dependences σ (T) is proposed, according towhich the compressed sample is represented by a system of crystallites with intergranular boundaries whoseproperties differ along and across the compression axis.

Based on the model of quantum flat rectangular and with infinitely high walls pit, the correspondences were calculated and received value of the Fermi energy and kinetic coefficients (conductivity σ, Seebeck coefficient S and thermoelectric power S2σ) for n-PbTe, by the Boltzman kinetic equation. Еhe cases with strongly degenerate and degenerate electronic gas in the films of lead telluride with n-type of conductivity are considered separately. The oscillating character of dependences of thermoelectric parameters of nanostructures based on n-PbTe for the degenerate and strongly degenerate electron gas has been theoretically proved.

The results of the study of thermoelectric properties and the defective subsystem of lead telluride doped by antimony PbTe:Sb (8%), promising material for the creation of heat energy converters on their basis. The regularities in the behavior of the properties investigated, which are due to the biphasicity of the material and the significant influence of the technological factors of obtaining samples on their defective subsystem, are established. The modeling of the defect subsystem of PbTe:Sb crystals was carried out taking into account thepresence of additional phase inclusions and it was found that dominant point defects are internode atoms of antimony.