Multiscale grain synergistic by microstructure designed hierarchically structured in BaTiO₃-based ceramics with enhanced energy storage density and X9R high-temperature dielectrics application

Dielectric capacitors are extensively applied in the electronics industry and energy storage fields due to their fast charging and discharging and better safety and stability. However, the inferior dielectric stability and low energy storage density observably limited the applications in electronics industry. A reasonable microstructural design of hierarchically structured ceramics by synergistic multiscale-domain is applied to the preparation of dielectric ceramics capacitors to improve the dielectric and energy storage properties. The dielectric and energy storage performance of materials could be adjusted and controlled by coordinating the single domain and multi domain structures of nanograins and macro grains. BaTiO₃-based dielectric ceramics are prepared by fabricating around macrocrystalline BaTiO₃ with nanocrystalline BaTiO₃. The synergistic effect for the various grain sizes of BaTiO₃ can significantly enhance the breakdown strength and polarization and achieve excellent dielectric properties. The results show that predominant dielectric temperature stability in compliance with the X9R standard is obtained. Synchronously, a large discharge energy storage density of 2.18 J cm⁻³ and an excellent energy storage efficiency of 77% together with prominent storage cycle stability (under 10⁵ times) and extraordinary temperature stability (30–200 °C) is achieved in this hierarchical structure design for BaTiO₃@FeO ceramics. The microstructure design by fabricated hierarchically structured materials provides a feasible illustration for developing dielectric capacitors with high-performance dielectric and energy storage capabilities.