Thermoelectric Properties of Nanostructured CoSb₃-Ceramic Composites

Kurzfassung

Thermal conductivity plays an important role for the effectiveness of CoSb3 Skutterudites as thermoelectric materials. The possibility of improving the figure-of-merit of unfilled CoSb3 by nanostructuring has been reported earlier. A key role in the preparation of these materials is the powder compaction by hot pressing to achieve dense solids without loosing the nanostructure by sintering processes. A new approach to this task is the usage of CoSb3-ceramic composites. ZrO2 powder with grain sizes on the nanometer scale is added to the Skutterudite material, acting as inert filler between the Skutterudite particles, thus reducing sintering. In the present work we investigate in more detail the effect of various pressing conditions on the thermoelectric properties (σ, κ, S) of both pure CoSb3 and alloyed material Co1- xNix(Sb1-yTey)3. These results are compared to those obtained from similar material with addition of ceramic powder.