High thermoelectric performance of single phase p-type cerium-filled skutterudites by dislocation engineering

Filled skutterudites, possessing a high power factor and good mechanical properties, have attracted intensive attention for the intermediate-temperature power generation. Since n-type filled skutterudites can achieve a high peak ZT of over 1.5, it is imperative to develop their high-performance p-type counterparts for real applications. In this work, single phase p-type cerium (Ce)-filled skutterudites with dense dislocation arrays were first fabricated by the liquid phase compaction method. It was demonstrated that the dense dislocation arrays significantly reduced the lattice thermal conductivity via strain scattering. Simultaneously, there was almost no influence on the normal carrier transport process. As a result, a high peak ZT value of over 1.1 at 723 K has been obtained for the liquid phase compacted Ce_0.8Fe₃CoSb₁₂ alloy, which is the record-high value among the single element-filled p-type skutterudites.