Low temperature synthesis of plate-like Na0.5Bi0.5TiO3 via molten salt method

In this study, plate-like Na0.5Bi0.5TiO3 (BNT) templates with perovskite structure were obtained by two-step molten salt synthesis (MSS) method at a low temperature. Firstly, Bi4Ti3O12 precursors were synthesized at 1030 degrees C in NaCl-KCl molten salt. Secondly, plate-like Na0.5Bi0.5TiO3 particles with perovskite structure were obtained from plate-like layer-structured ferroelectric ceramic of Bi4Ti3O12 by topochemical microcrystal conversion method. Result showed that excessive Na2CO3 was beneficial to facilitate the low temperature synthesis. In the case of an excess of 30 mol% Na2CO3, plate-like BNT particles could be obtained by synthesis at temperatures ranging from 760 degrees C to 800 degrees C, which indicated a flexible processing route. Also, it has been observed that plate-like BNT particles show a high aspect ratio with 1 mu m in thickness and 10-20 mu m in length. These Na0.5Bi0.5TiO3 plate-like particles can be good candidates for the preparation of lead-free BNT-based piezo-electric ceramics with oriented grain microstructure.