Effect of filling atoms onlattice thermal conductivity of LnyFexCo4-xSb12(Ln=Ce, Ba, Y)
X. F. Tang1, L. D. Chen2,T. Goto3, T. Hirai3, R. Z. Yuan1
1State Key Laboratory ofAdvanced Technology for Materials Synthesis and Processing, Wuhan University ofTechnology, Wuhan 430070, China
2State KeyLaboratory of High Performance Ceramics and Superfine Structure, ShanghaiInstitute of Ceramics, CAS, Shanghai 200050, China
3Institute for MaterialsResearch, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
Ce, Ba or Y were chosen as thefiller atom. Effects of kind of filling atom and filling fraction on latticethermal conductivity of LnyFexCo4-xSb12(Ln=Ce, Ba, Y) were investigated. Lattice thermal conductivity of LnyFexCo4-xSb12decreased significantly with an increasing Ce, Ba or Y filling fractionin the Sb-icosahedron voids. Lattice thermal conductivity of Ce or Ba filled(Ce, Ba)yFexCo4-xSb12 have peakvalues at about 40K, and show thermal conductivity characteristic of thecrystal. The peak values of lattice thermal conductivity of Y filled YyFexCo4-xSb12was not observed, indicating that YyFexCo4-xSb12shows a thermal conductivity characteristic of a glass. Y was more effectivethan Ce or Ba. To decrease the lattice thermal conductivity of filledskutterudite compounds Lattice thermal conductivity of LnyFexCo4-xSb12 reached a minimum values atcertain filling fraction, indicating that rattling effect of filling atoms wasthe strongest at certain filling fraction.