High Pressure Synthesis and Thermoelectric Properties of the Ba-filled Skutterudites

Polycrystalline skutterudite compounds BaxCo4Sb12(0.2 <= x <= 0.8) were successfully synthesized by solid state reaction under high pressure (2-5GPa). The crystallographic figures and microstructure were characterized by X-ray diffraction and electron probe microanalysis separately. Seebeck coefficient and electrical resistivity were measured at room temperature. The results show that high-pressure synthesis method can improve the Ba-filled content effectively. The samples have few micro-pores with fine-grained structure, their grain diameter sizes are in the micro-nanometer range. The maximum power factor value of the sample Ba0.8Co4Sb12 obtained at 4.25GPa is 13.19 mu W/(cm . K-2).