Thermoelectric Materials Based on Layered Chalcogenides of Bismuth and Lead

摘要

X-ray graphical and metallographic research and also study of thermoelectric properties of alloys of the triple relative system Pb, Bi || Se, Te according to cross sections of PbTe-Bi_2Se_3 and PbSe-Bi_2Se_3 were performed. It was shown that the PbTe-Bi_2Se_3 and PbSe-Bi_2Se_3 systems are not quasi-binary. In these systems, 51-, 12-, 57-, and 21-layered tetradymite-like phases which are isostructured to those existing in the quasi-binary system PbTe-Bi_2Se_3 were discovered. The coefficient of thermal EMF and electrical and heat conductivity were measured within the range of 80-360 K depending on the level of anion substitution. Investigation of the influence of anion substitution on the structure and properties of alloys of solid solutions with variable content of Se and constant cation-anion ratio was performed by example of alloys of solid solution PbBi_2(Te_(1-x)Se_x)_4 (0 < x < 0.9).