Thermoelectric Performance Enhancement of CeFe4Sb12 p-Type Skutterudite by Disorder on the Sb4 Rings Induced by Te Doping and Nanopores

Skutterudites have attracted a lot of attention because of the intrinsic voids in their crystal structure. However, another important structural feature of ptype skutterudites seems to have been ignored, namely the nearly square fourmembered antimony rings. To explore the influence of substitution of Te for Sb on the microstructure and thermoelectric properties, a series of p-type skutterudites with composition CeFe(4)Sb(12-x)Tex with x = 0, 0.1, and 0.2 have been synthesized. The electrical resistivity decreases while the Seebeck coefficient increases with Te doping. In addition, due to disturbance of the Sb4 rings and extra phonon scattering by nanopores, the lattice thermal conductivity is reduced. The thermoelectric figure of merit for the CeFe4Sb11.9Te0.1 compound reaches 0.76 at 773 K, being about 61% higher than that of the CeFe4Sb12 sample.