Ultrahigh capacitive energy storage of BiFeO3-based ceramics through multi-oriented nanodomain construction

Lead-free BiFeO₃-based (BF) materials with colossal spontaneous polarization and high Curie temperatures exhibit considerable potential for groundbreaking developments in dielectric capacitors. However, their inherent limitations, such as restricted breakdown strength (E_b) and pronounced remanent polarization, critically restrict advancements in energy storage capabilities. Herein, we achieve an exceptional recoverable energy density of 12.2 J cm^-3 with an impressive efficiency of 90.1% via the strategic design of a dipolar region with high resilience to electric fields within BiFeO₃-based ceramics. Guided by phase-field simulations and validated through atomic-scale observations, the superior energy storage performance is attributed to the incorporation of aliovalent ions, which disrupt the long-range ordered single-phase distribution, thus enhancing the disorder of polarization vectors and drastically reducing polarization hysteresis. Simultaneously, the refinement of the microstructural scale, coupled with the introduction of high-bandgap ions, synergistically improves the breakdown durability. This study provides a feasible blueprint for leveraging high-performance BiFeO₃-based ceramics, which further facilitates the progress of lead-free capacitors for next-generation energy storage systems.