Tailoring Phase Fraction Induced Saturation Polarization Delay for High-Performance BaTiO 3 -Based Relaxed Ferroelectric Capacitors.

Electrostatic capacitors based on dielectric materials are essential for enabling technological advances, including miniaturization and integration of electronic devices. However, maintaining a high polarization and breakdown field strength simultaneously in electrostatic capacitors remains a major challenge for industrial applications. Herein, a universal approach to delaying saturation polarization in BaTiO 3 -based ceramic is reported via tailoring phase fraction to improve capacitive performance. The ceramic of 0.85(0.7BaTiO 3 -0.3Bi 0.5 Na 0.5 TiO 3 )-0.15Bi 0.5 Li 0.5 (Ti 0.75 Ta 0.2 )O 3 delivers an ultrahigh recoverable energy density ( W rec ) of 7.16 J cm -3 along with an efficiency (η) of approximately 90% at a breakdown electric field of 700 kV cm -1 , outperforming the current BaTiO 3 -based ceramics and other lead-free ceramics. Meanwhile, the W rec and η exhibit wide frequency, temperature, and cycling fatigue stability. Additionally, both an extremely fast discharge time of 115 ns and a large power density of 106.16 MW cm -3 are concurrently attained. This work offers a promising pathway for delaying saturation polarization design in order to create scalable high-energy-density ceramics capacitors and highlight the research prospects of pulse power applications.