Abstract
The thermoelectric properties of polycrystalline Sr0.9RE0.1TiO3 (RE= Y, La, Sm, Gd, Dy) and Sr0.9-xBaxLa0.1TiO3 have been measured from room temperature to 873 K. The electrical conductivity and Seebeck coefficient of Sr0.9RE0.1TiO3, including their temperature dependences, are independent of the kind of rare earth elements. However, the thermal conductivity decreases according to ionic radius of the rare earth elements. So we can improve the figure of merit by decreasing of the thermal conductivity without deterioration of the electrical properties. Sr0.9Dy0.1TiO3 shows the highest value for the figure of merit, reaching 3.8×10-4 K-1 at 573 K. On the other hand, the electrical conductivity of Sr0.9-xBaxLa0.1TiO3 decreases with increasing of the Ba content. However, the figure of merit is increased near room temperature because of the low thermal conductivity.
