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 Ba 0.9 Ca 0.1 TiO 3 plate‐like grains with [110]‐crystal‐axis‐orientation. In the first step, plate‐like particles of a layered titanate H 1.07 Ti 1.73 O 4 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 Ba 0.9 Ca 0.1 TiO 3 . The formation reaction and nanostructure of the Ba 0.9 Ca 0.1 TiO 3 plate‐like grains were characterized using X‐ray diffraction, FE‐SEM , TEM , and SEAD . The Ba 0.9 Ca 0.1 TiO 3 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 Ba 0.9 Ca 0.1 TiO 3 plate‐like grains were utilized to fabricate an oriented Ba 0.9 Ca 0.1 TiO 3 ceramic to demonstrate the potential application of the plate‐like grains, and the [110]‐oriented Ba 0.9 Ca 0.1 TiO 3 ceramic with a high degree orientation of F 110 = 76% and small grain size of about 1–2 μm was obtained.