Thermal stability and improved electrical properties in Sr1−xGd2x/3Bi4Ti4O15 ceramics

We report improved electrical properties in Sr1−xGd2x/3Bi4Ti4O15 (SGBT-x, 0 ≤ x ≤ 0.1) ceramics prepared by solid state reaction route. The X-ray diffraction pattern suggested that the substitution lead to the formation of layered structure. Plate-like morphologies with decreasing grain size were clearly observed for all the samples. The temperature dependent dielectric analysis reveals that dielectric constant increases with increasing Gd3+ content up to x ≤ 0.08. Even excellent electrical properties (e.g., piezoelectric constant (d33) ∼19 pC/N, remanent polarization (2Pr) ∼0.38 µC/cm2 and Curie temperature (TC) ∼550 °C) are simultaneously obtained in the ceramic with x = 0.08. Additionally, thermal annealing studies indicated that the piezoelectric constant (d33) of the SGBT ceramics remains almost unchanged up to the transition temperature in all compositions.