Preparation and Thermoelectric Properties of Famatinite Cu3SbS4

Abstract

Famatinite Cu3SbS4 is considered to be a promising p-type thermoelectric material that consists of earth-abundant and nontoxic elements. In this study, this material was prepared by using mechanical alloying (MA) as a solid-state route and was consolidated using hot pressing (HP). The effects of MA–HP conditions on the phase synthesis (transformation) and thermoelectric properties were examined. Thermogravimetric and differential scanning calorimetric analyses confirmed that severe mass loss and endothermic reactions occurred at temperatures above approximately 750 K. This was possibly due to the melting of famatinite and the volatilization of the constituent elements. All the specimens exhibited p-type conduction and nondegenerate semiconductor characteristics. It was determined that the electrical and thermal conductivities decreased with an increase in the HP temperature, while the Seebeck coefficient increased. The thermal conductivity was lower than 0.74 Wm−1 K−1 at 623 K, and there was a small contribution of the electronic thermal conductivity to the thermal conductivity due to the intrinsically low electrical conductivity. The dimensionless figure of merit increased with increasing temperature, and the highest value was 0.14 at 623 K.