Growth of NBT template particles through topochemical microcrystal conversion and their structural characterization

Abstract

In this study, uniform rectangular plate-like perovskite Na0.5Bi0.5TiO3 templates were obtained by molten salt synthesis method in three steps. Perovskite plate-like Na0.5Bi0.5TiO3 templates were synthesized from bismuth-layered Na0.5Bi4.5Ti4O15 by topochemical microcrystal conversion method at the third and final step. The most important point was that the plate-like morphology remained as desired, but templates were obtained in cubic perovskite structure. The Na2CO3 excess in the third step was the main controlling parameter. The crystalline orientation of the particles was investigated by electron backscatter diffraction analysis. The results indicated that the particles are single crystalline in nature. In the case of the 90mol% excess of the stoichiometric Na2CO3 ratio, the NBT platelets had highly regular, rectangular prismatic morphology and single-crystal nature. The structure was also confirmed through high-resolution transmission electron microscope and selected area electron diffraction analysis.