Thermoelectric properties of Ag8GeTe6

Polycrystalline-sintered samples of Ag8GeTe6 were prepared and the electrical resistivity and Seebeck coefficient were measured from room temperature to about 800 K. The sample density is about 89% of the theoretical density. The electrical resistivity at room temperature is 1.87 x 10(-3) Omega m, which is about 100 times higher than that of Bi2Te3. The Seebeck coefficient is negative in the whole temperature range, showing that the majority of charge carriers are electrons. The value at room temperature is -123 mu VK-1. The thermal conductivity was measured only at 770 K. The value is 0.3 W m(-1) K-1, which is about one-third of that of Bi2Te3 (c) 2005 Elsevier B.V. All rights reserved.