Study on the dielectric properties and energy storage performance of BiFeO3–BaTiO3–SiO2 composites using core–shell nanoparticles

BiFeO3–BaTiO3–SiO2 nanocomposites were successfully developed from a conventional sintering process using core–shell nanoparticles, in which BaTiO3 was added to reduce the impact of defects and dividing domains to prevent the generation of leakage conductance, and the SiO2 coating layer was chemically coated on the nanoparticles to improve the density of the resulting nanocomposite. The dielectric properties, energy storage performance, and microstructure of nanocomposites were deeply explored, and the effect of SiO2 additives in different amounts was discussed. A decrease in leakage conductance was identified in the nanocomposites with an appropriate amount of SiO2 addition; as a result, the nanocomposites prepared from the nanoparticles coated with 10 wt. % silica exhibit a Pmax of 35.5 μC/cm2, Eb of 16 MV/m, and discharge energy density of 1.47 J/cm3, which demonstrated an effective strategy to develop inorganic composites for energy storage applications.