High pressure synthesis of p-type CeyFe4-xCoxSb12 skutterudites

Abstract

Co-substituted p-Type CeFe4-xCoxSb12 skutterudites were successfully synthesized with a high pressure synthesis method. The structure, composition, and thermoelectric properties were investigated. The obtained CeyFe4-xCoxSb12 samples show the skutterudite structure of Im3 symmetry. The hole concentration decreases with elevating Co substitution level, leading to increased Seebeck coefficient and electrical resistivity. Meanwhile, the filling fraction of Ce decreases, which is unfavorable for reducing the lattice thermal conductivity. As a result, the thermoelectric performance of CeyFe4-xCoxSb12 deteriorates with higher Co content. The maximal ZT of 0.91 was achieved at 763 K for the optimal Ce0.92Fe4Sb12 sample.