Synthesis and characterization of Bi0.5Na0.5TiO3-BaTiO3-K0.5Na0.5NbO3 ceramics for energy storage applications

Structural, microstructural, dielectric, ferroelectric and piezoelectric properties of the (0.95-x)Bi0.5Na0.5TiO3–0.05BaTiO3-xK0.5Na0.5NbO3 (BNT-BT-KNN) lead-free ceramics with 0.0 ≤ x ≤ 0.06 were studied. Samples were synthesized through the mechanochemically activated solid-state method and structurally characterized by X-ray diffraction (XRD) and Raman-spectroscopic studies, whereas the microstructure of all samples was analyzed by Field Emission Scanning Electron Microscopy (FE-SEM). When KNN concentration and temperature were increased, the transition from a ferroelectric to relaxor state was detected by ferroelectric-loop measurements. Furthermore, the high-energy storage efficiency values at room temperature obtained for samples with x ≥ 0.04 confirm the suitability of these ceramics for energy storage applications.