Thermoelectric properties of p-type Pb-doped Bi85Sb 15-xPbx alloys at cryogenic temperatures

In this study we have investigated the effect of the Pb on the thermoelectric propertied of Bi-Sb alloy with different Pb-content. The Pb-doped Bi85Sb15-xPbx (x = 0, 0.5, 1, 2, 3) alloys were synthesized by mechanical alloying followed by pressureless sintering. The crystal structure was characterized by X-ray diffraction. The Seebeck coefficients, electrical conductivities, and thermal conductivities were measured in the temperature range of 77-300 K. The results show that all the Pb-doped alloys are p-type thermoelectric materials in the whole measurement temperature range. A minimum thermal conductivity of 1.7 W/mK was obtained for Bi85Sb12Pb3 sample at 150 K. A maximum ZT value of 0.11, which is higher than those previous reported, was obtained for Bi 85Sb14Pb1 at 210 K. © 2011 Elsevier B.V. All rights reserved.