Thermoelectric properties of thallium antimony telluride

A polycrystalline sample of thallium antimony telluride, TlSbTe2, has been prepared and the thermoelectric properties, such as the electrical resistivity, Seebeck coefficient, and thermal conductivity have been measured. An ultrasonic pulse echo measurement has been performed to evaluate the elastic modulus and Debye temperature. The melting temperature has been measured by a differential thermal analysis. The electrical resistivity of TlSbTe2 is slightly higher than that of state-of-the-art thermoelectric materials, and has a positive temperature dependence. The Seebeck coefficient of TlBiTe2 is positive in the whole temperature range, showing p-type semiconductor behavior. The thermal conductivity of TlBiTe2 is relatively low compared with that of state-of-the-art thermoelectric materials. The maximum value of the thermoelectric figure of merit ZT is 0.87 at about 715 K. (C) 2004 Elsevier B.V. All rights reserved.