The effects of 4% barium doping on the morphological, strutural and dielectric characteristics of (Na0.5 Bi0.5)[(Ti0.8 Zr0.2)0.9(Nb2/3 Zn1/3)0.1]O3

Abstract

In this study, perovskite ceramics (Na0.5 Bi0.5)1-xBax[(Ti0.8 Zr0.2)0.9(Nb2/3 Zn1/3)0.1]O3 (NB1- xBxTZNZ) were prepared using the molten salt method. The sintering process was conducted at 1100°C for 4 hours in an air atmosphere. The crystal structure was examined using X-ray powder diffraction, which indicated that the material crystallized in a tetragonal structure with a space groupe P4bm. However, there was also evidence of 6% pyrochlore phase present. The crystallite size was found to decrease with Barium doping, and this decrease was attributed to the pinning effect of grain boundaries resulting from the formation of oxygen vacancies which reduce the AC conductivity values. Scanning electron microscopy was employed to examine the grain morphologies, revealing that the sample exhibited a compact structure. Additionally, the density of (NB1-xBxTZNZ) (x=0.04) was observed to be higher compared to (NB1-xBxTZNZ) (x=0.00). Barium doped into NB1-xBxTZNZ also caused a decrease in dielectric constant and dielectric loss. Raman spectroscopy was performed at room temperature on the doped ceramic with Barium, and we discussed the incorporation of Ba2+ in A-site of the perovskite ABO3.