Laminated ferroelectric polymer composites exhibit synchronous ultrahigh discharge efficiency and energy density via utilizing multiple-interface barriers

Due to their superior dielectric and breakdown properties, nonlinear ferroelectric-based hierarchically structured composites have shown tremendous promise in applications such as film capacitors. However, because of the high field-dependent dominant conduction loss, a long-lasting challenge is to synchronously achieve high energy storage density (U-e) at greater than 90% efficiency (eta) with great mechanical reliability using ferroelectric polymer-based hierarchically structured composites. Herein, a solution-processable tri-layered arrangement of polymeric films is elaborately proposed that utilizes multiple interface barriers. In this structure, decreased high-field conduction loss and increased energy storage capability result from the synergy between a macro interbedded interface and a micro-orientation interface. The tri-layered composite assumed a recording capacitive property by utilizing 50 wt% linear polymethyl methacrylate/poly(vinylidene fluoride-co-hexafluoropropylene) (PMMA/P(VDF-HFP)) blends as outer layers and P(VDF-HFP) incorporated with 2.5 vol% aligned two-dimensional strontium titanate plates as the inner layer. This resulted in an enormous approximately 800% enhancement of the maximum energy storage with greater than 90% efficiency over state-of-the-art dielectric polymers and hierarchically structured composites. The results of the rigorous winding test (720 hours) indicated excellent energy storage stability. Thus, this work provides a feasible method to construct high-performance ferroelectric-based polymer composites for capacitive energy storage.