Sodium bismuth titanate-based perovskite ceramics with high energy storage efficiency and discharge performance

Designing dielectric materials with the tremendous energy storage density is fundamentally important for developing pulse power capacitors. An effective approach was proposed to favorably modify the dielectric energy storage properties (ESP) of Bi0.5Na0.5TiO3 ceramics using CaTiO3 incorporation. The dielectric breakdown strength was effectively enhanced, and simultaneously the relaxor behavior was optimized to lower the remnant polarization, which is resulted from the decreased grains size with the introduction of Ca2+ ion. Remarkably, at a CaTiO3 doping level of 0.2, a 0.8Bi0.5Na0.5TiO3-0.2CaTiO3 (0.8BNT-0.2CT) ceramic obtained both high energy storage density (Wtotal) of ∼1.38 J/cm3 together with excellent efficiency (η) of ∼91.3%. Furthermore, an ultrafast discharge response speed (t0.9) ∼ 94 ns was achieved in 0.8BNT-0.2CT ceramic, as well as tremendous current density (CD ∼1520 A/cm2) and power density (PD ∼115 MW/cm3). This study not only revealed the superior ESP mechanism as regards Bi0.5Na0.5TiO3 based ceramics but also provided candidate materials in pulse power capacitor devices.