Abstract
The effect of mechanical grinding (MG) on the thermoelectric properties of the skutterudite material CoSb3 was examined. The sign of the thermoelectric power (a) of CoSb3 which was not exposed to MG treatment (no-MG-sample) was positive, while that of CoSb3 which was exposed to MG treatment (MG-sample) was negative. With an increase of temperature, the electrical resistivity (ρ) of no-MG-sample increases, but that of MG-sample decreases. The thermal conductivity (k) of the material was decreased by MG treatment, which are ascribed to the decrease of the grain size by the MG treatment. The figure of merit (Z=α2/(ρ⋅k)) of no-MG-sample is larger than that of MG-sample in the temperature range from room temperature to 500°C.
