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Information × Registration Number 0220U103418, 0117U007146 , R & D reports Title Thermoelectric materials based on modified thallium(I)- and copper (I)-containing chalcogenides popup.stage_title Head Malakhovska Tetiana О., Registration Date 01-10-2020 Organization State University "Uzhhorod National University" popup.description2 For the first time the phase equilibria in multicomponent systems Tl–Pb–Te, Tl2Te (Tl5Te3)−Tl4SnTe3–Tl4PbTe3, Cu7PSe6–CuBr(I)–Cu2Se, and Cu7PS6–Cu7PS5Br(I) were studied, the boundaries of existence of phases and coordinates of singular points were established. The crystal structure of intermediate compounds were established, the mechanisms of formation of solid solutions based on complex thallium (I) tellurides and copper (I) halogensulfides (selenides) were investigated, which made it possible to establish "composition-property" correlations. For the first time, in the Cu7PSe6 – Cu2Se system the existence of a new congruently melting (1058 K) quaternary γ-phase (5Cu2Se: 8Cu7PSe6) was established. For the first time, technological conditions for the synthesis and growth of high-quality single- and polycrystalline samples were developed, for which thermoelectric and electrophysical properties were studied. By modifying the composition of ternary tellurides Tl4Sn(Pb)Te3, it was possible to select the optimal composition of the solid solution sample and increase the Seebeck coefficient (300-600 K) by 2-30 times. Established that the maximum values of thermoelectric power are possessed by samples of quaternary halogenchalcogenides: Cu6PS5Br(I) (PF from 31.66 to 89.13 µW/m×K2) and solid solutions of Cu6.1PS5.1Br0.9, Cu6.25PS5.25Br0.75, Cu6.1PS5.1I0.9, they are recommended for the manufacture of laboratory samples of medium-temperature energy converters. Established a significant influence of atmospheric air on the value of the Seebeck coefficient for the single-crystalline sample of individual ternary compound Cu7PS6, which can have practical use, in particular for sensor systems.   Product Description popup.authors Kohutych Anton Antonovych Pohodin Artem Ihorovych Filep Mykhailo Yosypovych popup.nrat_date 2021-03-17 Close