Utilizing the phonon glass electron crystal concept to improve the thermoelectric properties of combined Yb-stuffed and Te-substituted CoSb3

A cost-effective and rapid mechanical alloying method was used to prepare Yb-stuffed and Te-substituted CoSb3 to study the thermoelectric properties of this material. Yb rattles inside the cage-like structure of CoSb3 which effectively reduces the phonon mean free path and results in a lattice thermal conductivity comparable to those of costly nanostructured CoSb3 materials. A very low lattice thermal conductivity of 1.17 W m−1 K−1 at ∼550 K was obtained. A zT value of ∼0.7 was reported at 600 K due to the very low lattice thermal conductivity.