HPHT synthesis and electrical transport properties of SmxCo4Sb12

Samarium-filled skutterudites SmxCo4Sb12 (x=0.5, 1.0) skutterudite thermoelectric (TE) materials with enhanced power factor were prepared by high-pressure and high-temperature (HPHT) technique. The microstructure properties were characterized with X-ray diffraction and scanning electron microscopy. The electrical resistivities and Seebeck coefficients of those samples were measured in the temperature range of 300–723 K, and the samples of SmxCo4Sb12 showed n-type conduction. The Seebeck coefficient in absolute value of SmxCo4Sb12 increased with an increase of temperature and decreased with an increase of x. Among all the samples, Sm0.5Co4Sb12 showed the highest power factor of 2.5×10−3 W/m/K2 at 665 K. The results indicated that HPHT combined with samarium filling is an effective way to enhance the thermoelectric properties for skutterudite compounds.