Domain structure of Bi4Ti3O12 ceramics revealed by chemical etching

Chemical etching of bismuth titanate (Bi4Ti3O12) ceramics was developed using a mixture of different agents based on HF, NH4F and H2O. Thermal etching modifies the surface morphology and this give place to rounded plate-like grains. Suitable etching of Bi4Ti3O12 samples could be however achieved with chemical agents, because it preserves the original shape of the platelets. Furthermore with this kind of etching two relevant features of the microstructure arise in scanning electron microscopy (SEM) micrographs: the domain structure of the etched grains and the presence of square-shaped holes inside the platelets.