Core–satellite Ag@BaTiO3 nanoassemblies for fabrication of polymer nanocomposites with high discharged energy density, high breakdown strength and low dielectric loss

Abstract

Dielectric polymer nanocomposites with high dielectric constant have wide applications in high energy density electronic devices. The introduction of high dielectric constant ceramic nanoparticles into a polymer represents an important route to fabricate nanocomposites with high dielectric constant. However, the nanocomposites prepared by this method generally suffer from relatively low breakdown strength and high dielectric loss, which limit the further increase of energy density and energy efficiency of the nanocomposites. In this contribution, by using core-satellite structured ultra-small silver (Ag) decorated barium titanate (BT) nanoassemblies, we successfully fabricated high dielectric constant polymer nanocomposites with enhanced breakdown strength and lower dielectric loss in comparison with conventional polymer-ceramic particulate nanocomposites. The discharged energy density and energy efficiency are derived from the dielectric displacement-electric field loops of the polymer nanocomposites. It is found that, by using the core-satellite structured Ag@BT nanoassemblies as fillers, the polymer nanocomposites can not only have higher discharged energy density but also have high energy efficiency. The mechanism behind the improved electrical properties was attributed to the Coulomb blockade effect and the quantum confinement effect of the introduced ultra-small Ag nanoparticles. This study could serve as an inspiration to enhance the energy storage densities of dielectric polymer nanocomposites.

Enhanced dielectric and energy storage density induced by surface-modified BaTiO3 nanofibers in poly(vinylidene fluoride) nanocomposites

“…However, to achieve high dielectric constants for nanocomposites, a high volume fraction of ceramic filler is normally required, which simultaneously decreases the flexibility of the nanocomposite. Moreover, breakdown strength drops off precipitously with the high proportion of ceramic fillers due to an increased defect density, agglomeration of fillers, as well as percolation with the low dielectric strength ceramic fillers [27]. That leads to very minor enhancement of energy-storage density as compared with the pure polymer matrix.…”

Core-satellite BaTiO3@SrTiO3assemblies for a local compositionally graded relaxor ferroelectric capacitor with enhanced energy storage density and high energy efficiency

“…In companies with such kinds of energy generation, energy storage technologies are urgently demanded for efficient utilization of the power produced from these renewable sources. [5][6][7][8] In recent years, towards the miniaturization, light weight and integration of electric and electronic devices, capacitors with high energy storage density are becoming distinctly important. 3 Capacitors which intrinsically possess a high power density and a fast charge/discharge capability are promising candidates for energy storage devices.…”

Significantly Enhanced Energy Storage Density by Modulating the Aspect Ratio of BaTiO3 Nanofibers

“…In addition, recent studies have demonstrated that the morphology and geometry of ceramic nanoparticles influence the dielectric properties of nanocomposites222324. For 0–3 type ceramic-polymer nanocomposites, where spherical zero-dimensional ceramic nanoparticles are embedded in a three-dimensionally connected polymer matrix, a high volume fraction (>50 vol%) of nanoparticles is necessary to achieve a high permittivity nanocomposite.…”