Abstract: Skutterudite compound Co_4-xNi_xSb₁₂ was synthesized by the melting method and its thermal and electrical properties were measured in the temperature range of 300～850K. The carrier concentration and electrical conductivity increase with increasing Ni content substituting for Co. The absolute value of Seebeck coefficient decreases and T opt of Seebeck coefficient shifts to a higher temperature with the increase of Ni content. These different transport behaviors in the samples are ascribed to the introduction of extra electrons to the Skutterudite structure by Ni substitution. The lattice thermal conductivity of Co_4-xNi_xSb₁₂ is significantly depressed as compared to that of CoSb₃ by introducing extra electron-phonon scattering mode. The maximum ZT value obtained for Co_3.92Ni_0.08Sb₁₂ at 750K is about 0.55.

Key words: Ni doping, skutterudite, thermoelectric transport properties