Structural, piezoelectric and highdensity energy storage properties of lead-free BNKT-BCZT solid solution

A solid solution of lead-free piezoelectric ceramic (1-x)Bi0.50(Na0.80K0.20)0.50TiO3-xBa0.90Ca0.10Ti0.90Zr0.10O3 (with x = 0.00, 0.02, 0.04, 0.06, 0.08) was synthesized by conventional solid-state reaction route. The effect of addition of BCZT on BNKT was investigated on structural, microstructural, dielectric, ferroelectric, piezoelectric and high-density energy storage properties experimentally. Modified Curie Weiss law and Vogel-Fulcher law were employed to study the diffusivity and activation energy. The dielectric dispersion with frequency reveals the relaxor behavior for all compositions. The value of Tv (calculated from Vogel-Fulcher relation) decreases while the corresponding value of Ea increases with the BCZT composition. The unipolar curve shows the increased strain of 0.15% and corresponding d33∗ (Smax/Emax = 311 pm/V) for x = 0.02 composition among all studied compositions. Furthermore, compositions x = 0.02 and x = 0.04 shows the improved energy storage efficiency ∼50% with respect to pure BNKT.