Ferroelectric properties of Pr6O11-doped Bi4Ti3O12

Praseodymium doped Bi4Ti3O12 (BIT) ceramics with composition Bi2.9Pr0.9Ti3O12 (BPT) were prepared by solid state reaction. These samples have polycrystalline Bi-layered perovskite structure without preferred orientation, and consist of well-developed plate-like grains with random orientation. Pr doping into BIT causes a large shift of the Curie temperature (TC) of the BIT from 675 to 398 °C. At an electric field of 87 kV/cm, the remanent polarization and the coercive field of the BPT ceramics are 30 μC/cm2 and 52 kV/cm, respectively. Furthermore, the dielectric permittivity and the dissipation factor of the BPT ceramics are 300 and 0.003 at 1 MHz, 1 V, and room temperature. Ferroelectric properties of the BPT ceramics are superior to V-doped Bi4Ti3O12 (∼20 μC/cm2 and 80 kV/cm) and (Sr, Ta)-doped Bi4Ti3O12 (∼12 μC/cm2 and 71 kV/cm) ceramics. In addition, the dense ceramics of praseodymium-doped B4Ti3O12 were obtained by sintering at 1100 °C, about 100–200 °C lower than those of the SrBi2Ta2O9 system.