Synthesis and characterization of Na0.5Bi0.5TiO3 platelets with preferred orientation using Aurivillius precursors

Plate-like Na0.5Bi0.5TiO3 (NBT) templates with perovskite structure were successfully synthesized by a topochemical microcrystal conversion (TMC) method from Aurivillius precursors, Bi4Ti3O12 (BIT) and Na0.5Bi4.5Ti4O15 (NBIT) platelets. Both NBT platelets and their precursors showed a high aspect ratio between an average size of 10–20 μm and thickness of 0.5–1.0 μm. The clear lattice fringe and the diffraction spots of BIT, NBIT and NBT platelets obtained from high-resolution transmission electron microscopy (HRTEM) indicated good crystallinity. The NBT platelets showed a high degree of preferred pseudocubic [001] orientation with a large Lotgering factor of 0.87 which exhibited good potential as suitable templates for synthesizing textured lead free piezoelectric ceramics, e.g. Na0.5Bi0.5TiO3–xBaTiO3, via the templated grain growth process.