Ferroelectricity in intergrowth Bi3TiNbO9–Bi4Ti3O12 ceramics

Monophase intergrowth Bi3TiNbO9–Bi4Ti3O12 (BTN-BIT) ceramics were synthesized by solid-state reaction method. In the temperature dependence of dielectric permittivity, two anomalies appeared at 945 and 1114K, respectively. The ferroelectric hysteresis loop measurement revealed that the 2Pr is 20μC∕cm2, nearly as twice as that of the BTN ceramic. The crystal structure analysis indicated that the enhanced octahedral distortion along the a axis is the main contribution to the ferroelectricity of BTN-BIT. The increased 2Pr for the BTN-BIT ceramics is ascribed to its larger Ps than that of the BTN and easier domain switching under electric field than that of the BIT.