Enhanced electric polarization and breakdown strength in the all-organic sandwich-structured poly(vinylidene fluoride)-based dielectric film for high energy density capacitor

It is essential to develop the dielectric energy storage capacitor for the modern electrical and electronic equipment. Here, the all-organic sandwich-structured composite with superior breakdown strength and delayed saturation polarization is presented. Furthermore, the energy storage characteristics of the composite are enhanced by the poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) fiber and the redistribution of local electric field. The dielectric permittivity of composite increases to ∼16, and the discharged energy density is high to ∼8.7 J/cm³ at 360 kV/mm, and the breakdown strength is up to ∼408 kV/mm. The excellent performance of the composite broadens the application in the field of power electronics industry.