Preparation of Crystal-Axis-Oriented Barium Calcium Titanate Plate-Like Particles and Its Application to Oriented Ceramic

A novel two‐step process has been developed for the preparation of Ba0.9Ca0.1TiO3 plate‐like grains with [110]‐crystal‐axis‐orientation. In the first step, plate‐like particles of a layered titanate H1.07Ti1.73O4 are solvothermally treated in a Ba(OH)2–Ca(OH)2 mixed solution, and then in the second step, heat‐treat the solvothermally treated sample to complete the formation reaction of Ba0.9Ca0.1TiO3. The formation reaction and nanostructure of the Ba0.9Ca0.1TiO3 plate‐like grains were characterized using X‐ray diffraction, FE‐SEM, TEM, and SEAD. The Ba0.9Ca0.1TiO3 plate‐like grains are constructed from spherical nanoparticles with particle size of about 10–20 nm. The spherical nanocrystals in each plate‐like grain arrange in the same crystal‐axis‐orientation direction, which presented a diffraction pattern similar to the single crystal. The Ba0.9Ca0.1TiO3 plate‐like grains were utilized to fabricate an oriented Ba0.9Ca0.1TiO3 ceramic to demonstrate the potential application of the plate‐like grains, and the [110]‐oriented Ba0.9Ca0.1TiO3 ceramic with a high degree orientation of F110 = 76% and small grain size of about 1–2 μm was obtained.