Optimization of energy storage properties in (1 - x)Na0.5Bi0.5TiO3-xSr0.7La0.2TiO3-relaxed ferroelectric ceramics

Ferroelectric materials are considered to be the most competitive energy storage materials for applications in pulsed power electronics due to excellent charge-discharge properties. However, the low energy storage density is the primary problem limiting their practical application. In this study, (1 - x)Na0.5Bi0.5TiO3-xSr(0.7)La(0.2)TiO(3)[(1 - x)NBT-xSLT] ferroelectric ceramics are found to exhibit excellent energy storage performances through a synergistic strategy. As the SLT concentration increases, the relaxation characteristic increases significantly and the breakdown strength increases dramatically from 150 kV/cm to 220 kV/cm. The recoverable energy storage density of the 0.55NBT-0.45SLT ceramic is 2.86 J/cm(3) with an energy storage efficiency of 88% under an electric field of 220 kV/cm. Furthermore, the ceramic with x = 0.45 mol exhibited excellent energy storage stability in the ranges of 20-180 degrees C (temperature) and 1-125 Hz (frequency). These excellent properties demonstrate the potential of (1 - x)NBT-x SLT ceramics when used as dielectric capacitors in pulsed power systems.