Structure and Morphology of Nanocrystalline BZT Powders Prepared Using Hydrothermal Method

The nanocrystalline of BaZrxTi1-xO3 (BZT) (where x= 0, 0.001 and 0.008) powders have been prepared by hydrothermal method at 150 o C for 2h using as prepared titanium tetraclouride, zirconium oxyclouride and barium hydroxide as starting materials. They were investigated by x-ray diffraction XRD, transmission electron microscopy TEM, selection area electron diffraction SAED and high resolution transmission electron diffraction HRTEM. The BaTiO3 (BT) nanocrystals have a cubic perovskite structure and they convert to tetragonal perovskite after annealing at temperature 700 o C while BZT convert it at higher than 700 o C as revealed by XRD. It is found that the increased in Zr content caused a decreased in tetragonallity factor. The morphology of BT powders showed a star shape and dendrites pattern, not very smooth surfaces and non uniform in contrast while the dendrites pattern is absence in BZT as a result of TEM. There is a high contract variation in the TEM images of BT and BZT which indicates the presence of strains inside the lattice. The SAED results indicate a perfect crystal structure and HRTEM images revealed the presence BZT powders that showed small nucleated islands at the edges of the faceted particles of the prepared BT.