Influence of zirconium doping on structure, microstructure, dielectric and impedance properties of strontium bismuth niobate ceramics

• We report influence of substitution of Zr4+ for Nb5+ in SrBi2Nb2O9.
• Higher Curie temperature was observed for SrBi2(Nb2−(4/5)xZrx)O9 with x = 0.1.
• Maximum peak dielectric constant was observed for SrBi2(Nb2−(4/5)xZrx)O9 with x = 0.1.
• SEM revealed change in shape of grains to elongated plate structure with the Zr substitution.

Efforts have been made in this work to enhance the dielectric properties of SrBi2Nb2O9 (SBN) by partial substitution of Zr4+ for Nb5+. Systematic investigations on structure, microstructure, dielectric and impedance properties of the SrBi2(Nb2−(4/5)xZrx)O9 [where, x = 0, 0.1 and 0.2] ceramic samples were carried out to understand the effect of substitution of Zr4+ for Nb5+ in SrBi2Nb2O9. The X-ray diffraction (XRD) investigations indicated that the lattice volume of SrBi2(Nb2− (4/5)xZrx)O9 with x = 0.1 and 0.2 decreases compared to SBN. The SEM investigations revealed an increase in the size of grains and the change on shape of grains to elongated plate shaped structure with the increase of x (x = 0.1 and 0.2) in SrBi2(Nb2−(4/5)xZrx)O9. Higher Curie temperature and enhanced peak dielectric constant at the Curie temperature were observed for both the SrBi2(Nb2−(4/5)xZrx)O9 with x = 0.1 and 0.2 ceramic samples compared to SBN. Among the investigated compositions the higher Curie temperature and enhanced peak dielectric constant at the Curie temperature was observed for SrBi2(Nb2−(4/5)xZrx)O9 with x = 0.1.