Studying some of physical properties of barium titanate (BaTio3) prepared by using freeze-drying method.

number: 
766
إنجليزية
department: 
Degree: 
Imprint: 
Physics
Author: 
Awes Emad Mugheer
Supervisor: 
Dr. Emad K. Al- Shakarchi
Dr.Fadhel A. Rasen
year: 
2002
Abstract:

A fine and homogenous powder of Barium Titanate (BaTiO3) has been prepared using freeze drying method, and studied the physical properties through different techniques such as; the X-ray diffraction (XRD), Fourier Transform Infrared spectrum (FTIR), Scanning Electron Microscopy (SEM), and surface area measurements. The synthesis process of freeze drying method starts by mixing complex a Catechol (C6H4(OH)2) and Titanium Clorid (TiCU), with a suitable amount of them, dissolved in dry Toluene. Then add Barium Carbonarc (BaCO3) solution that was prepared previously. The final product is an aqueous solution of Barium Titanium - Catechol complex (Ba[Ti(cat)3] ). This solution sprayed on liquid nitrogen with a droplets using glass spray system. The freeze dryer apparatus used under vacuum (10² mbar) and low temperature (- 30°C) to investigate the sublimation process of the frozen droplets to produce fine homogenous powder. The produced powder undergoes to different thermal treatments through the sintering process by temperatures 600, 800, 1000, and 1100°C. Then the product expected to be a Barium Titanate (BaTiO3) powder. Different measurements used to study the physical properties related to high homogeneity powder such as XRD, FTIR, SEM, and surface area measurements. It was found from XRD- technique that the required structure was cubic with lattice constant (13.26615 °A at 600°C),( 13.453 °A at 800°C ),( 13.621 °A at 1000°C) and ( 13.813 °A at 1100°C) and confirmed this result with result obtained by FTIR. SEM- measurements exhibited the surface morphology of (BaTiO3) through the shape of grains and grain boundaries. It is concluding that the grain size in range of (0.4—0.7 u.m) and confirmed these results with result obtained by surface area measurements.