Solvothermal soft chemical synthesis and characterization of plate-like particles constructed from oriented BaTiO3 nanocrystals

Abstract

Plate-like BaTiO3 particles with a size of about 200 nm in thickness and 3 μm in width were prepared by using a novel solvo-thermal soft chemical process in ethanol and water-ethanol mixed solvents. A layered titanate of H1.07Ti1.73O4 with a lepidocrocite-like structure and plate-like nanoparticle morphology was used as the precursor, and solvothermally treated in the Ba(OH)2 solution to prepare the BaTiO3 nanoparticles. The formation reaction, particle morphology, nanostructure, and crystal-axis-orientation of the plate-like BaTiO3 nanoparticles were studied by XRD, FE-SEM, and TEM. The plate-like BaTiO,3 nanoparticles are formed by an in situ topotactic structural transformation reaction. The crystallinity and particle morphology can be controlled by changing the fraction of ethanol in the solvent, Ba(OH)2 concentration, and reaction temperature. The plate-like BaTiO3 nanoparticles are polycrystalline particles constructed from spherical nanocrystals which are arranged in the same crystal-axis orientation in each plate-like particle, and show a high degree orientation in [110] direction, being suitable for preparing oriented BaTiO3 ceramic materials with high performance. © 2010 The Ceramic Society of Japan.