Low-temperature transport properties of the mixed-valence semiconductor Ru0.5Pd0.5Sb3

Abstract
We have measured the transport properties of Ru0.5Pd0.5Sb3 from 300 down to 4 K and compared them to those of the binary‐skutterudite antimonides. In particular, the lattice thermal conductivity of this compound is substantially lower than that of CoSb3 and IrSb3. This is attributed to the mixed‐valency of ruthenium in this compound. Using near‐edge extended absorption fine structure analysis, it is observed that ruthenium in this compound is in the Ru4+‐ and Ru2+‐valence states in approximately equal proportions. The potential for thermoelectric applications of this material is also discussed.