Multilayer polymer nanocomposites based on interface engineering for high-performance capacitors

Polymer film capacitor is a critical component for high-power application. Due to the low energy density of conventional polymer dielectrics, polymer film capacitor has gradually failed to meet the requirements of miniaturization of the energy system. Thus various strategies to improve the energy density of polymer di-electrics have been reported in the past decades. Remarkably, the construction of multilayer-structure com-posites has attracted extensive interest from researchers because of their unique electrical properties. However, the reviews on the design principles of multilayer dielectrics have still not been comprehensive and systematic so far, especially for the potential regulation mechanism of multilayer interfaces. In this review, recent progress in polymer-based multilayer-structure composite dielectrics based on multilayer interface engineering has been summarized, which includes charge injection, density of surface states, enhanced interface polarization, interface barrier, and common preparation of multilayer polymer films. The summary and outlook for future research directions of multilayer polymer films are also provided in this review.