Sintering and dielectric properties of Sr(Bi2Ta2)1−xTi4xO9 ceramics

The influence of Ti4+ substitution on the dielectric properties of Sr(Bi2Ta2)1−xTi4xO9 (SBTT) ceramics (x up to 0.2) has been studied. The sintering temperature of SBTT slightly decreases as the TiO2 content increases with the partial substitution of Bi2O3 and Ta2O5 by TiO2. X-ray diffraction analysis on SBTT ceramics with low TiO2 content and sintered at lower temperature indicate that single-phase layered perovskite ferroelectrics are obtained and no TiO2 phase is found, while the TiO2 crystal phase increases with the TiO2 content and sintering temperature. The incorporation of Ti4+ into SrBi2Ta2O9 results in a shift of the Curie temperature to higher values than for SrBi2Ta2O9. Nevertheless, the Curie temperature is not a function of sintering temperature and TiO2 content.