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 (Eb) 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.