Enhanced energy density of polymer composites filled with BaTiO3@Ag nanofibers for pulse power application

High-energy-density flexible composite films, using one dimension BaTiO3@Ag nanofibers (BT@Ag NFs) as fillers and PVDF as polymeric matric, have been prepared by solution casting and the following hot compressing molding. The BT@Ag NFs have been prepared by electrospinning and then chemical deposition method. The dielectric constant, dielectric loss, breakdown strength and energy density were studied systematically. The maximum dielectric constant is 42.8 at 1 kHz in the nano-composites loading with 15 vol% BT@Ag NFs, which is about 515% larger than that of the pristine PVDF (8.3 at 1 kHz). The energy density of the 2.5 vol% BT@Ag NFs/ PVDF nanocomposites is 7.75 J cm(-3) at 3500 kV m(-1), which is about 645% over the biaxially oriented polypropylenes (1.2 J cm(-3) at 6400 kV m(-1)). The enhanced energy density may be ascribed to the Coulomb block effect. Such improvements are of potential importance for preparation of high-energy-density nanocomposites.