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

In this study, uniform rectangular plate‐like perovskite Na_0.5Bi_0.5TiO₃ templates were obtained by molten salt synthesis method in three steps. Perovskite plate‐like Na_0.5Bi_0.5TiO₃ templates were synthesized from bismuth‐layered Na_0.5Bi_4.5Ti₄O₁₅ 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 90 mol% 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.