Synthesis of BaTiO_3 and Ba(Zr_xTi_1 -x)O3 by using the Soft Combustion Method

摘要

In this work, barium titanate, BaTiO_3 (BT) and Zr doped BT, BaZr_xTii-_xO_3 (BZT) with powders were successfully produced using the soft combustion method. Barium nitrate and titanium (IV) isopropoxide were used as the starting materials while zirconium (IV) oxynitrate hydrate as the doping precursors, and glycine as the combustion agent. The produced powders were pressed into 12 mm diameter pellets by using 150 MPa cold press. The effect of Zr dopant inBT was studied with molar ratio of x= 0.00, 0.03, 0.05, 0.08 and 0.10. The phase presence was identified using X-ray diffractometer. Morphology of powders and sintered pellets was observed using a scanning electron microscope. Density of the sintered pellets was measured by using Archimedes' principle, while dielectric properties were analysed by using an LCR meter. Pure perovskite BT and BZT structure were obtained after sintering at 1400 °C for 5 h. BZT with x= 0.03 has grain size of 3.9 μm and shows the highest dielectric constant of 525, compared to undoped BT that has the average grain size of 4.2 μm with dielectric constant 223. The results is in agreement with micro structure observation and density of the sample.