Electrical properties of Ag1-xPb18SbTe20 (x=0, 0.1. 0.3)

A sintered polycrystalline sample of Ag1-xPb18SbTe20 (x = 0, 0.1, 0.3) was prepared by a solid-state reaction. The electrical resistivity and Seebeck coefficient were measured from room temperature to about 800 K. The electrical resistivity of Ag1-xPb18SbTe20 (x = 0, 0.1. 0.3) decreases with increasing Ag content. The values of the electrical resistivity are of the order of 10(-4) Omega m. The Seebeck coefficient of Ag1Pb18SbTe20 is positive up to 420 K, however, it changes to negative from 420 to 800 K. The absolute value of the Seebeck coefficient of Ag1-xPb18SbTe20 (v = 0.1, 0.3) at 373 K is 404 and 320 muV K-1, respectively, which is twice as high as that of state-of-the-art thermoelectric materials. (C) 2004 Elsevier B.V. All rights reserved.