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20 , що у першому випадку зумовлено значним ростом електропровідності матеріалу, а у двох інших -як збільшенням коефіцієнту термо-ЕРС, так і значним зниженням теплопровідності у порівнянні з бездомішковим PbTe.Ключові слова: плюмбум телурид, легування, тверді розчини, LAST, термоелектричні властивості.Стаття поступила до редакції 15.10.2014; прийнята до друку 15.12.2014.

The recent discovery of excellent thermoelectric properties and topological surface states in SnTe-based compounds has attracted extensive attention in various research areas. Indium doped SnTe is of particular interest because, depending on the doping level, it can either generate resonant states in the bulk valence band leading to enhanced thermoelectric properties, or induce superconductivity that coexists with topological states. Here we report on the vapor deposition of In-doped SnTe nanowires and the study of their surface oxidation and thermoelectric properties. The nanowire growth is assisted by Au catalysts, and their morphologies vary as a function of substrate position and temperature. Transmission electron microscopy characterization reveals the formation of amorphous surface in single crystalline nanowires. X-ray photoelectron spectroscopy studies suggest that the nanowire surface is composed of In 2 O 3 , SnO 2 , Te and TeO 2 which can be readily removed by argon ion sputtering. Exposure of the cleaned nanowires to atmosphere yields rapid oxidation of the surface within only one minute. Characterizations of electrical conductivity σ, thermopower S, and thermal conductivity κ were performed on the same In-doped nanowire which shows suppressed σ and κ but enhanced S yielding an improved thermoelectric figure of merit ZT than the undoped SnTe. 2

The results of the researching of thermoelectric properties of samples, which are obtained by compressing mechanical mixtures of microdisperse powders PdTe and CdTe, are presented. It was found that the using of cadmium for telluride as an additional component to the lead telluride contributes to a decrease in the coefficient of thermal conductivity of the materials of the studied system, which can be promising for the creation of thermoelectric converters based on them.