Characterization of structure and dielectric properties of solid state synthesized (1-x)Bi0.5 Na0.5 TiO3 - xBaTiO3 ceramic around the MPB region

Abstract

Dielectric and structural properties of energy storage (1-x) Bi0.5Na0.5-xBaTiO3(x=0.04,0.06,0.0S) ceramics were analyzed by preparing the samples by conventional solid state sintering method. Since electrical properties of ceramics are strongly influenced by the density, a close examination of it has been presented by a graph. XRD results ensured the formation of the perovskite structure and a tetragonal-rhombohedral morphologic phase boundary was located in 0.06$\leq x\leq$0.08 range, which demonstrated the superior dielectric properties. Growing BT concentration inhabited the grain growth which was revealed by SEM analysis. All BNT-BT samples had a superior dielectric constant, being in the order 928-990 which were determined room temperature at 1 Hz frequency. The highest value of dielectric constant was $8_{\text{r}}=988$, which was achieved by the same sample with x$=0.08$ at (1-x)BNT-xBT. All these results exhibit that, 0.92BNT-0.08BT fabricated by solid-state sintering method is a promising lead-free ceramics with excellent structural and electrical properties.