Multifilled nanocrystalline p-type didymium – Skutterudites with ZT > 1.2

The influence of double, triple and multi-filling of didymium, Ca, Ba, Sr and Yb in Fe3CoSb12 on the thermoelectric performance was investigated. Ball-milling followed by hot pressing was used for sample preparation to gain dense and nanostructured samples. Almost all of the samples studied in this work have a ZT higher than 1, some even reach ZT > 1.2 at 700 K or at 800 K and an average ZT up to 1.0 in the temperature range from 300 K to 800 K. Thermal expansion, hardness and the elastic moduli were investigated exemplarily for two alloys with ZT > 1.2. With these results we can claim to have very promising p-type skutterudites for thermoelectric devices.