Preparation and thermoelectric properties of some phosphide skutterudite compounds

Thermoelectric properties of CoP3 and CeFe4P12 have been measured. These co mpounds were synthesized by a flux technique using Sn as the solvent. The s amples were characterized by x-ray diffractometry and electron microprobe a nalyses. The Seebeck coefficient, the electrical resistivity, the Hall effe ct, and the thermal conductivity were measured over a wide range of tempera tures. The results indicate that CoP3 and CeFe4P12 are semiconductors, in a greement with theoretical predictions. The thermal conductivity of CeFe4P12 is about 10 times larger than that for CeFe4Sb12 which is primarily due to both reduced motion of the Ce ions in smaller voids and lower hole-phonon scattering. The results are analyzed and discussed to provide guidelines fo r optimization of the thermoelectric properties of these materials. (C) 199 9 American Institute of Physics. [S0021-8979(99)03923-7].