Preparation and thermoelectric properties of AgPb18SbTe20−xSex (x = 1, 2, 4) materials

AgPb18SbTe20−xSex (x = 1, 2, 4) bulk materials were prepared by combining hydrothermal synthesis and melting. Thermoelectric properties were measured from room temperature up to 773K. The materials showed n-type conduction and exhibited degenerate semiconductor behavior. The power factors of the materials varied greatly with increase of Se content (x). Partial substitution of Se for Te in AgPb18SbTe20 resulted in remarkable reduction of thermal conductivity in the whole temperature range and increase of power factor at lower temperatures; therefore, the dimensionless figure of merit, ZT, was enhanced below 600K. A maximum ZT value of ∼0.82 is obtained at 523K for the AgPb18SbTe18Se2 sample.

► In this work we studied AgPb18SbTe20 material.
► The material was prepared by combining hydrothermal synthesis and melting.
► The effect of Se doping on the thermoelectric properties of the material was studied.
► Se doping resulted in markedly reduction of thermal conductivity.
► Se doping resulted in increase of power factor at lower temperature.