Abstract
We have prepared Zn1-xAlxO ceramics by the polymerized complex method and examined the microscopic structure and thermoelectric properties comparing with the results of the sample prepared by the solid state reaction method. A small amount of ZnAl2O4 spinel phase which increases with increasing x was observed in the hot-pressed samples with x ≥ 0.02 by x-ray diffraction and SEM. The grain size of the sample by the polymerized complex method is much smaller than that of the sample by the solid state reaction method. The electrical resistivity and the absolute value of the Seebeck coefficient for the sample by the polymerized complex method are smaller than those for the sample by the solid state reaction method. The carrier contribution to the thermal conductivity of the sample by the polymerized complex method is larger than that of the sample by the solid state reaction method in the whole temperature range, while the phonon contribution to the thermal conductivity at low temperature of the sample by the polymerized complex method is smaller than that of the sample by the solid state reaction method. These behaviors are ascribed to the difference of the carrier concentration and the grain size between these samples.
