摘要
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.
