High energy storage performance in poly(vinylidene fluoride)-based all-organic composites via optimizing the structure of semiconductive filler

The great demand for miniaturization and lightweight energy equipment stimulates the fast development of polymer-based dielectrics with low density and easy processability. Unfortunately, the low energy density puts barriers to the development of polymer dielectrics in the new energy industry. In this work, poly(vinylidene fluoride) (PVDF)-based blending films are prepared and the energy storage properties are explored by regulating the content and structure of semiconductive polymer fillers. The experiment results show that when poly{2-((3,6,7,10,11-pentakis(hexyloxy)triphenylene-2-yl)oxy)ethyl methacrylate} (P6) filler is added, 0.25 wt%-P6/PVDF film attains the maximal discharge energy density (U_d) of 19.1 J cm⁻³ at 624 MV m⁻¹. Compared with poly{2-((3,6,7,10,11-pentabutoxytriphenylen-2-yl)oxy)ethyl methacrylate} (P4) filler, the P6 filler possesses better compatibility with PVDF and creates deeper traps to suppress the carrier migration and achieve the higher breakdown strength. This research offers useful references for the design of polymer-based composites with excellent energy density through blending triphenylene semiconductive fillers.