Ferroelectric polymers are the materials of choice for capacitive energy storage owing to their highest dielectric constants (K) and the best energy densities among the current dielectric polymers. Herein, different from the conventional approaches based on the incorporation of high-K fillers into the single-layer films to enhance the capacitive performance, a low-K polymer, i.e. PMMA with a K value of 3–4, is selected as an example and introduced into the layered configurations of the ferroelectric polymer. Both improvements in the energy density (U_e) and charge–discharge efficiency (η) over those of the pristine polymer have been achieved via the establishment of multiple interlaminar interfaces and modulation of component ratios. The influence of film configuration on the capacitive performance has been systematically studied. The trilayered all-polymer film with optimized component ratio is capable of operating with a charge–discharge efficiency as high as 84% and concurrently delivering an energy density up to 20.3 J cm⁻³, surpassing the capacitive performance of the currently available polymer dielectrics that present the upper limits of U_e of ~20 J cm⁻³ and η of ~80%. Along with excellent stability of dielectric and mechanical properties of the polymer films, this work suggests great potential of the multicomponent ferroelectric polymers with layered architecture for electrical energy storage applications.

铁电聚合物由于其目前的介电聚合物中最高的介电常数（K）和最佳的能量密度而成为电容性储能的首选材料。在此，与基于将高K填料掺入单层薄膜以增强电容性能的常规方法不同，以低K聚合物（即K值为3-4的PMMA）为例。并引入到铁电聚合物的分层结构中。能量密度（U _e）和充放电效率（η）均得到改善）通过建立多个层间界面和调节组分比可以达到原始聚合物的1）。已经系统地研究了膜结构对电容性能的影响。具有最佳成分比率的三层全聚合物膜能够以高达84％的充放电效率运行，并同时提供高达20.3 J cm ^-3的能量密度，超越了目前可用的聚合物电介质的电容性能目前的U _e的上限为〜20 J cm ^-3和η〜80％。聚合物膜具有优异的介电稳定性和机械性能，这项工作表明具有分层结构的多组分铁电聚合物在储能方面的巨大潜力。