Optimization of energy-storage properties with low electric field applications in Ca0.5Sr0.5TiO3-based linear ceramics by establishing relaxor ferroelectrics

Given superior breakdown strength than ferroelectrics, linear dielectrics have garnered plenty of attention, yet their low polarization restricts practicability at low electric fields. Hence, a strategic approach for optimizing the energy storage performance of Ca0.5Sr0.5TiO3 ceramics by selecting 0.75 K0.5Bi0.5TiO3-0.25BiFeO3 as a modulating element to establish relaxor ferroelectrics is put forward in this study. Owing to the incorporation of 0.75 K0.5Bi0.5TiO3-0.25BiFeO3 with high polarization, the issue of low polarization in Ca0.5Sr0.5TiO3 linear ceramics is overcame. (1-x)Ca0.5Sr0.5TiO3-x(0.75 K0.5Bi0.5TiO3-0.25BiFeO3) (CST-x(KBT-BF)) ceramics reveal a conversion from linear dielectrics to relaxor ferroelectrics, accompanied by a high polarization (>45 μC/cm2) and recoverable energy density of 3.11 J/cm3 under 180 kV/cm, along with remarkable frequency and temperature stability. Simultaneously, the stepped-up relaxor behavior and refined grain size conduce to improve the energy storage performance. CST-0.5(KBT-BF) ceramics exhibit likewise a commendable discharge power density of 18.7 MW/cm3 and an ultra-short discharge time of 46.7 ns at 80 kV/cm. This work set up a conspicuous paradigm to promote the innovation-driven development of advanced energy storage capacitors at low electric fields.