Thermoelectric properties of Cu-doped p-type pseudo-binary CuxBi0.5Sb1.5−xTe3 (x = 0.05–0.4) alloys prepared by spark plasma sintering

Measurements conducted on the Cu-doped CuxBi0.5Sb1.5−xTe3 (x = 0.05–0.4) alloys show that their electrical conductivities are approximately 8.6 and 2.3 times those of the ternary Bi0.5Sb1.5Te3 alloy at room temperature and 558 K, respectively, and reveal a drastic reduction of lattice thermal conductivities after Cu doping. The highest dimensionless figure of merit ZT of 1.2 is achieved for the materials with x = 0.05 at 442 K, being approximately 2.1 times that of typical ternary Bi0.5Sb1.5Te3 alloy at room temperature.