Thermoelectric properties of hot-pressed YbAl3 compound over temperature range 150-800 K

Small crystals of YbAl₃ have been obtained using the Bridgman or a direct synthesis method and subsequently disc-shaped compacts prepared using a hot-pressing technique. The Seebeck coefficient, electrical resistivity, thermal diffusivity and specific heat capacity were measured over a temperature range 200-800 K. Although the thermal conductivity of YbAl₃ is much higher than that of Bi₂Te₃ based alloys, YbAl₃ possesses an electrical power factor which is more than double those of Bi₂Te₃ based alloys. The thermoelectric figure of merit at room temperature is about 1.1×10^-3 K^-1 , which is only a third of Bi₂Te₃ based thermoelectric materials. However, YbAl₃ may be a useful material for electrical power generation using waste heat with its substantially large electrical power factor providing a large electrical power density