Solvothermal Soft Chemical Synthesis and Characterization of Nanostructured Ba_1–x(Bi_0.5K_0.5)_xTiO₃ Platelike Particles with Crystal-Axis Orientation

This paper introduces a Ba 0.5 (Bi 0.5 K 0.5 ) 0.5 TiO 3 (BBKT) platelike particle constructed from cuboidlike nanocrystals which arrange in the same crystal-axis-orientation direction. This platelike particle is synthesized via a novel two-step solvothermal soft chemical process. In the first step, platelike particles of a layered titanate H 1.07 Ti 1.73 O 4 (HTO) precursor is solvothermally treated in Ba(OH) 2 solution to obtain platelike particles of a BaTiO 3 –HTO (BT–HTO) nanocomposite. In the second step, the nanocomposite particles are hydrothermally treated in BiCl 3 –KOH solution to obtain the BBKT platelike particles. The formation reaction and nanostructure of the BBKT platelike particles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), and energy-dispersive spectroscopy (EDS). BBKT platelike particles prepared via this method present an SAED pattern similar to the single crystal, although it is a polycrystalline particle. All the BBKT nanocrystals in each platelike BBKT particle have the same orientation to the [110]-direction. There is a definite relationship between the crystal-axis directions of the HTO precursor and the BBKT product.