Double-filled skutterudites InxPryCo4Sb12, which are currently being investigated
for potential applications as thermoelectric materials, have been successfully
prepared by inductive melting and annealing. Our results showed
that In and Pr double filling effectively improves both electrical conductivity
and Seebeck coefficient compared with pristine or single-filled CoSb3, giving
rise to a respectable power factor. The largest power factor, 2.33 m Wm1 K2,
was achieved at 609 K for In0.05Pr0.05Co4Sb12; this value is approximately
three times that for InxCo4Sb12 (x £ 0.3) skutterudites. These results imply
that In and Pr double filling are better than In single filling for efficient
improvement of the thermoelectric properties of CoSb3 skutterudite.