Anisotropic ferro- and dielectric properties of textured Bi 4Ti3O12 ceramics prepared by the solid-state reaction based on multiple calcination

Abstract

The grain-oriented Bi4Ti3O12 (BIT) samples were prepared by the solid-state reaction method with a multicalcination process. The grain-oriented BIT samples exhibit anisotropic structural, ferroelectric, piezoelectric, and dielectric properties. The remanent polarization (2 Pr) and the piezoelectric constant (d 33) of a/b- and c-direction BIT ceramics are 49.5μCcm-2, 22.2 pC N-1 and 6.7μCcm-2 6.9 pC N-1, respectively. The dielectric anomalies of samples are observed around 157K and 232K. The dielectric anomalies at around 157 K are related to oxygen vacancies. The activation energy of the dielectric relaxation of this anomaly is estimated to be 1.36eV. Another dielectric anomaly at around 232K is related to polarizable domains and the viscous motion of domain walls. Copyright © 2010 Xiangyu Mao et al.