Thermoelectric and Transport Properties of Permingeatite Cu(3)SbSe(4) Prepared Using Mechanical Alloying and Hot Pressing

Permingeatite (Cu(3)SbSe(4)) 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 Cu(3)SbSe(4) 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 Cu(3)SbSe(4) prepared using MA at 350 rpm for 12 h and HP at 573 K for 2 h.