THERMOELECTRIC FIGURE OF MERIT IN (AGSB)1-ХPBХSE2 SINGLE CRYSTALS

Abstract

This article is devoted to studies the dependence of the thermal conductivity coefficient and thermoelectric figure of merit in (AgSb)1-xPbxSe2 single crystals on their composition. We found that the lattice component provides the main contribution to the thermal conductivity of solid solutions (AgSb)1-xPbxSe2 at x=0-0,4. The electronic thermal conductivity in single crystals with values of x at 0,92-1, becomes close to the lattice component. An increase in the Pb fraction of (AgSb)1-xPbxSe2 in the range from x=0 to x=0,4 leads to a decrease in the thermal conductivity (AgSb)1-xPbxSe2 from 0.56 W / K · m to 0.27 W / K · m, and an increase in x from 0,92 to 1 leads to an increase in the thermal conductivity in the range from 0,45 W / K · m to 1,11 W / K · m. The thermoelectric figure of merit was the highest in all compositions: (AgSb)1-xPbxSe2 at x = 0, 0,1, 0,2 0,92, 1 (ZT≈0,014-0,46). Having a high value of the thermoelectric figure of merit, single crystals of such composition are promising materials for thermoelectric energy generation. The smooth change of thermoelectric properties (AgSb)1-xPbxSe2 with a formation in the content of Pb atoms can find practical use in semiconductor instrumentation, where AgSbSe2 and PbSe materials are used.