Preparation and Thermoelectric Properties of Ag0.5In0.5−xPb5Sn4Te10

A series of compounds with composition Ag0.5In0.5−xPb5Sn4Te10 (x = 0.05 to 0.20) were prepared by slowly cooling the melts of the corresponding elements, and the effect of In content on the thermoelectric transport properties of these compounds has been investigated. Results indicate that the compounds’ electronic structure is sensitive to In content, and that the carrier concentration of these compounds at room temperature increases from 4.86 × 1018 cm−3 to 3.85 × 1021 cm−3 as x increases from 0.05 to 0.20. For these compounds, electrical conductivity decreases and Seebeck coefficient increases with increasing In content. Ag0.05In0.03Pb0.5Sn0.4Te10 shows very low lattice thermal conductivity, and has a maximum dimensionless figure of merit ZT of 1.2 at 800 K.