Achieving high energy storage in BaTiO₃/rGO/PVDF nanocomposites by regulating the charge transfer path at the hetero-interface

Superior energy storage performance of PVDF-based nanocomposites such as discharged energy density or efficiency is reported, leading to a lower volume, lightweight system, or high reliability for film capacitors. However, researchers often ignore exploring practical ways to simultaneously enhance the discharged energy density (U-e) and energy storage efficiency (eta) as well as the physical mechanism that determines the energy storage performance. Herein, the charge transfer path in the PVDF matrix with core-shell nanoparticles under 150 MV m(-1) was first analyzed by finite element simulation. Under the guidance of theoretical simulation, core-shell structured BaTiO3 (BTO)@reduced graphene oxide (rGO) nanoparticles (NPs) were introduced into the PVDF matrix, in which rGO played the trapping role. The introduction of rGO reduces the possibility of local electric field failure of composite materials, optimizing the charge transfer path and improving both U-e and eta, which are superior to the data in the literature. An effective strategy for creating high-energy storage polymer nanocomposites is presented in this study.