Barium Titanate Prepared by Stearic Acid-Gel Method

Stearic acid-gel method was used to prepare barium titanate. All the samples show a cubic perovskite structure and thus no ferroelectricity is detected at room temperature. X-ray diffraction reveals that the grains can hardly grow even firing at high temperature so that the grain size in most of the samples is below the ferroelectric critical size. A tentative explanation is proposed of the peculiarities based on the nonstoichiometry at the surface layer.