Ferroelectric and Optic Properties of the Translucent BaTiO3 Ceramics Derived from Nanocrystalline Monolith

ABSTRACT Polycrystalline, translucent barium titanate (BaTiO3) ceramics were successfully fabricated from partially crystallized, transparent monolithic xerogels produced by a high concentration sol-gel method using metal alkoxides. The xerogels yielded dense and translucent BaTiO3 ceramics after heat treatment at 1100°C for 1 h in oxygen flow, with an average grain size of about 0.5 μ m and a relative sintered density of 97%. The transmittance of a ceramic (0.2 mm thick) was observed to increase almost linearly with wavelength of light, showing a transmittance of 32% at 800 nm. The dielectric constant of the ceramics at room temperature was found to be 1500, and the remanent polarization and coercive field were 2 μ C/cm2 and 5 kV/cm, respectively. The variation of transmittance for a ceramic as a function of applied electric field to examine the material's electro-optic property was also measured.