Energy storage performance of sandwich structure composites with strawberry-like Ag@SrTiO3 nanofillers

Recent years witness a rapid surge in the research efforts on dielectric capacitors due to their high power density and fast charge/discharge speed. However, the relatively low energy density demands more efforts to meet the lightweight and compact requirement for practical applications. Here, we report sandwich-structured nano-composite films with strawberry-like Ag@SrTiO3 nanofillers. The introduction of Ag nanoparticles (NPs) on SrTiO3 NPs could significantly improve dielectric properties, breakdown strength, energy storage density, and efficiency. As a result, a dramatically enhanced discharged energy density (24.6 J/cm(3)) and efficiency (86.3%) are reached in sandwich-structured nanocomposite films containing 1.5 wt% Ag@SrTiO3 nanofillers by the so-lution casting method. The enhancement of dielectric constant and breakdown strength of nanocomposite films is attributed to the Coulomb-blockade effect of Ag NPs, which inhibits the transformation of electrons. Our finite element simulation explicitly demonstrates that the Coulomb-blockade effect of Ag NPs can effectively improve energy storage performance, which therefore supports the experimental results.

Automated summary

In recent years, research efforts on dielectric capacitors have increased rapidly due to their high power density and fast charge/discharge speed. To meet the lightweight and compact requirement for practical applications, researchers have reported sandwich-structured nano-composite films with strawberry-like Ag@SrTiO3 nanofillers. The introduction of Ag nanoparticles has significantly improved dielectric properties, breakdown strength, energy storage density, and efficiency.