Hydrothermal Synthesis of Spherical Bismuth Titanate Crystals

Spherical bismuth titanate (Bi4Ti3O12) particles were synthesized by hydrothermal method using Bi(OH)(3), Ti(SO4)(2) and KOH as raw materials, using polyvinylpyrrolidone (PVP) as the surfactant. The effects of concentration of the alkali solution, the reaction temperature and soaking time on the bismuth titanate crystal structure and morphology have been analyzed. XRD, SEM were used to characterize the crystal structure and microstructure of the as-prepared Bi4Ti3O12. The results show that the temperature plays an important role on the morphology of the Bi4Ti3O12. As the increase of the hydrothermal temperature, the Bi4Ti3O12 has been transformed from the spherical morphology to fibrous morphology. The spherical Bi4Ti3O12 powders with uniform distribution can be obtained when the concentration of KOH is from 1mol/L to 2 mol/L, the reaction temperature and hydrothermal time are 160 degrees C and 24h respectively. SEM observation showed that the diameter of spherical Bi4Ti3O12 is about 500 nm.