ТЕРМОЕЛЕКТРИЧНІ ВЛАСТИВОСТІ ЕВТЕКТИЧНИХ СПЛАВІВ КВАЗІПОТРІЙНОЇ СИСТЕМИ SnSe2–TlBiSe2–Bi2Se3

Abstract

The eutectic alloys of a quasiternary system SnSe2–TlBiSe2–Bi2Se3 are synthesized. Samples for measurings prepared by the way of pressed polycrystals. The thermoelectric properties studied by a Harman method in temperature range 300–600 K. Is established, that the two-component eutectic composition (Bi2Se3)0.70(TlBiSe2)0.30 has low electrical conductivity and falls into to n-type of semiconductors. The two-component eutectic (SnSe2)0.67(Bi2Se3)0.33 has high thermoelectric performance Zt=0,94×10-3 K-1 at 595 K. Third dual eutectic alloys of a composition (SnSe2)0.55(TlBiSe2)0.45 is characterized by the best parameters of thermoelectric performance Zt≈2×10- 3 K-1 at 536 K. Alone ternary eutectic alloys in this system (SnSe2)0,49(Bi2Se3)0,27(TlBiSe2)0,24 has low parameters Zt<0,1×10-3 K-1 in all the learnt temperature interval. Taking into consideration maximum of value of thermoelectric performance of source reductants and learnt eutectics, the most perspective areas in ternary system SnSe2–TlBiSe2–Bi2Se3 for looking up new thermoelectrics are determined. Is established, that new effective composition, most likely, are on sections е2–е3, е3–TlBiSe2, SnSe2–е3, е3–Е1, and also in conditional areas SnSe2–е2–е3 and е2–е3–Е1. The offered scheme of the plotting of increase of thermoelectric performance of eutectic alloys and other intermediate phases is possible to use by consideration other ternary chalcogenides systems.