Enhanced energy storage properties of BNT-based ceramics via composition and multiscale structural engineering

Under the background of the urgent development of electronic components towards integration, miniaturization and environmental protection, it is of great economic value to research ceramics with large energy storage density (Wrec) and high efficiency (η). In this study, the ceramics of (1-x)Bi0.5Na0.5TiO3-xSrTi0.8Ta0.16O3 ((1-x)BNT-xSTT) are prepared to explore the relationship between energy storage properties and multiscale structure. With increasing the content of STT, the rhombohedral phase of BNT becomes pseudo-cubic phase, the average grain size is refined, the resistivity is improved, and the concentration of oxygen vacancy is decreased, hence the dielectric breakdown strength (Eb) is significantly promoted from 120 kV/cm for BNT to 245 kV/cm for 0.6BNT-0.4STT. Eventually, the 0.65BNT-0.35STT ceramic exhibits a large Wrec of 3.3 J/cm3 and a high η of 90.4% under 230 kV/cm, showing outstanding potential in pulse power systems.