Influence of samarium substitution on the ferroelectricity of Bi 4 Ti 3 O 12 ceramic.

Bismuth titanate (BT-‘Bi4Ti3O12’) is one of the extensively studied materials of the Bismuth layered structure ferroelectric (BLSF) family for its large spontaneous polarization along c-axis. In the present investigation, we have synthesised SmxBi4-xTi3O12(x = 0.37, 0.57, 0.72) ceramics using the conventional solid-state reaction method. The dielectric anomaly was observed near 450°C. Well-broad hysteresis loops were observed above room temperature up to 100°C. The coercive field (Ec) and consistent remanent polarization (Pr) values with temperature, compared to BT, indicates that the title compound has good promising ferroelectric-nature. This phenomenon is attributed to the easy recovery of defects (such as oxygen vacancies) accumulated at grain-interfaces, above room temperature, resulting in to well-hysteresis behaviour. The results were further confirmed with remanent polarization (2 Pr vs. temperature) plots. [ABSTRACT FROM AUTHOR]