Thermal Conductivity of Fe-Doped Cosb3 Skutterudites

Abstract

AbstractWe investigate the effect of Fe substitution for Co on the lattice thermal conductivity of CoSb3 skutterudites. The polycrystalline materials are formed from uniaxially hot-pressed powders. Three alloys were prepared with 0, 3% and 10% Fe, respectively. Thermal conductivity measurements were made between 80 K to 450 K. The lattice thermal conductivity of 10%Fe:CoSb3 is approximately two times smaller than the lattice thermal conductivity of CoSb3 over the entire temperature range. This effect cannot be accounted for by the phenomenlogical theory considering only the mass difference and strain field due to the alloying (Fe) atom. Other phonon scattering mechanisms are discussed. Comparison is made with the partially-filled skutterudite alloy, La0.65Fe2.8Co1.1Sb12.