Thermoelectric and Transport Properties of Permingeatite Cu3SbSe4 Prepared Using Mechanical Alloying and Hot Pressing

Abstract

Permingeatite (Cu₃SbSe₄) is a promising thermoelectric material because it has a narrow band gap, large carrier effective mass, and abundant and nontoxic components. Mechanical alloying (MA), which is a high-energy ball mill process, has various advantages, e.g., segregation/evaporation is not required and homogeneous powders can be prepared in a short time. In this study, the effects of MA and hot-pressing (HP) conditions on the synthesis of the Cu₃SbSe₄ phase and its thermoelectric properties were evaluated. The electrical conductivity decreased with increasing HP temperature, while the Seebeck coefficient increased. The power factor (PF) was 0.38-0.50 mW m^-1 K^-2 and the thermal conductivity was 0.76-0.78 W m^-1 K^-1 at 623 K. The dimensionless figure of merit, ZT, increased with increasing temperature, and a reliable and maximum ZT value of 0.39 was obtained at 623 K for Cu₃SbSe₄ prepared using MA at 350 rpm for 12 h and HP at 573 K for 2 h.

Keywords: hot pressing; mechanical alloying; permingeatite; thermoelectric.