Synthesis of textured Bi5Ti3FeO15 and LaBi4Ti3FeO15 ferroelectric layered Aurivillius phases by molten-salt flux methods

The ferroelectric layered Bi5Ti3FeO15 and LaBi4Ti3FeO15 Aurivillius phases were synthesized in high purity and textured microstructures in a molten Na2SO4/K2SO4 (1:1 molar ratio) flux in much shortened reaction times, 1 h minimum compared to conventional techniques. The particle growth and microstructure of both phases were investigated as a function of temperature and reaction duration, and yielded plate-like particles that could be synthesized in sizes from <1 μm to >20 μm. The product crystallinity, purity and microstructures were characterized via powder X-ray diffraction and scanning electron microscopy. The UV–vis diffuse reflectance of the products were measured and analyzed with respect to the resultant particle sizes.