Ferroelectric polymers and their nanocomposites for dielectric energy storage applications

Dielectric capacitors deliver the highest power density and operating voltage among known energy storage devices that are integrable in modern electronic and electrical systems. Ferroelectric polymers are promising dielectric energy storage media for film capacitors due to their superiority in excellent dielectric properties, high breakdown strength, and flexibility. Polymer-based nanocomposites by incorporating high-dielectric-constant nanofillers into the ferroelectric polymer matrix exhibit great potential for superior energy storage performances. This Perspective focuses on the development and progress of high-energy-density ferroelectric polymers and their nanocomposites. First, approaches are proposed to tune the ferroelectric hysteresis for suppressed dielectric and energy losses in ferroelectric polymers, which is the premise to achieve high energy density and high efficiency. Second, the energy storage properties of ferroelectric nanocomposites greatly depend on multiple factors such as nanofiller features, polymer/filler interfaces, and spatial composite structures, and effective strategies enabling enhancements of the dielectric constant and breakdown strength in nanocomposites are discussed. In the last part, some existing challenges and future perspectives are proposed to develop high-energy-density ferroelectric polymer-based materials for energy storage applications.