SYNTHESIS OF Bi5TiNbWO15 CERAMICS

In the present study bismuth containing ceramic material Bi5TiNbWO15, belonging to the family of mixed-layer Aurivillius phases have been synthesized and fabricated. The compounds were synthesized according to the solid state reaction by mixed oxide method. The process of preparation was investigated by simultaneous thermal analysis and X-ray powder diffraction method. It was found that the structure adopted the polar orthorhombic space group 12cm, a=5.4318 angstrom, b=5.4255 angstrom, c=41.6382 angstrom. Impedance spectroscopy was applied to characterize polarization processes present in the system and to separate the bulk, grain boundary, and electrode processes of polycrystalline ceramic material. The Kramers-Kronig data validation test was employed in the present impedance data analysis. Apart from the Nyquist (i.e., Z" vs. Z') and Bode (i.e. vertical bar Z vertical bar vs.) plots the alternative representations of impedance spectra were used to reveal contributions with relatively small differences in relaxation frequencies.