Synthesis and Electrical Properties of Ba_yFe_xCo_4-xSb₁₂

Abstract

Filled skutterudite compounds, Ba_yFe_xCo_4-xSb₁₂ (x=0-3.0, y=0-0.7), were synthesized by a two step solid state reaction method. Electrical transport properties of Ba_yFe_xCo_4-xSb₁₂ were investigated. The lattice constants of Ba_yFe_xCo_4-xSb₁₂ increased with increasing Ba filling fraction and Fe content. The maximum filling fraction of Ba (y_max) in Ba_yFe_xCo_4-xSb₁₂ increased with increasing Fe content, and was found to be rather greater than that of Ce_yFe_x Co_4-xSb₁₂. The y_max, varied from 0.35 to near 1.0 when Fe content (x) changed from 0 to 4.0. Carrier concentration and electrical conductivity increased with increasing Fe content, and decreased with increasing Ba filling fraction for Ba_yFe_xCo_4-xSb₁₂. At the same x and y, carrier concentration and electrical conductivity of Ba_yFe_xCo_4-xSb₁₂ were larger than that of Ce_yFe_xCo_4-xSb₁₂.