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Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/35393
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Документ Effect of cold pressing on the concentration dependences of thermoelectric properties of (Bi1-xSbx)2Te3 solid solutions (x = 0 – 0.07)(FOP Mezina, 2018) Martynova, K. V.; Rogacheva, E. I.Документ Thermoelectric properties of polycrystalline Bi₁₋ₓSbₓ solid solutions in the concentration range x = 0 – 0.25(National Academy of Sciences of Ukraine, 2016) Doroshenko, A. N.; Rogacheva, E. I.; Drozdova, A. A.; Martynova, K. V.; Men'shov, Yu. V.A detailed investigation of the dependence of thermoelectric properties of polycrystalline Bi₁₋ₓSbₓ solid solutions on composition in a wide concentration range (x = 0 – 0.25) was performed at room temperature. The objects of study were cast samples of various composition obtained by ampoule method in one technological cycle consisting in cooling of ampoules with melts in the air and subsequent long homogenizing annealing at temperature (520 ± 5) K for 720 hours. It was shown that the composition dependences of properties are of clearly expressed nonmonotonic type. The presence of concentration anomalies of thermoelectric properties was confirmed that had been earlier observed in the range x = 0 – 0.1 on cast samples after different kinds of thermal treatment and interpreted as manifestation of electron phase transitions. A complicated nature of dependences at x > 0.1 is attributable to qualitative changes in Bi₁₋ₓSbₓ band structure at certain critical compositions, a change in relative contribution to conductivity of charge carriers from different energy bands with a change in antimony concentration and high sensitivity of energy spectrum and physical properties of Bi₁₋ₓSbₓ к to external effects.Документ Thermoelectric and mechanical properties of (Bi₁₋ₓSbₓ )₂Te₃(x = 0÷0.07) semiconductor solid solutions(National Academy of Sciences of Ukraine, 2016) Rogacheva, E. I.; Martynova, K. V.; Bondarenko, A. S.The dependences of thermoelectric properties and microhardness on the composition of polycrystalline (Bi₁₋ₓSbₓ )₂Te₃ solid solutions in the concentration range x = 0÷0.07 at room temperature were investigated. A drastic growth of microhardness was discovered with a simultaneous reduction of the Hall coefficient, the Seebeck coefficient and electric conductivity with increase in antimony content x = 0.005 – 0.01, following which with further increase in x to x = 0.01 – 0.015, the type of the dependences was reversed. The observed effect is attributable to a high degree of crystal lattice disorder with the introduction of the first portions of impurity and to subsequent relaxation processes with formation of percolation channels in crystal impurity subsystem. With further increase in x, the Hall coefficient and the Seebeck coefficient practically do not change with composition, and the observed more complicated dependence of microhardness and electric conductivity on x is interpreted as a manifestation of short-range processes in a solid solution.