Significantly Elevated Dielectric and Energy Storage Traits in Boron Nitride Filled Polymer Nano-composites with Topological Structure

Abstract

Interface induced polarization has a prominent influence on dielectric properties of 0–3 type polymer based composites containing Si-based semi-conductors. The disadvantages of composites were higher dielectric loss, lower breakdown strength and energy storage density, although higher permittivity was achieved. In this work, dielectric, conductive, breakdown and energy storage properties of four nano-composites have been researched. Based on the cooperation of fluoropolymer/alpha-SiC layer and fluoropolymer/hexagonal-BN layer, it was confirmed constructing the heterogeneous layer-by-layer composite structure rather than homogeneous mono-layer structure could significantly reduce dielectric loss, promote breakdown strength and increase energy storage density. The former worked for a larger dielectric response and the latter layer acted as a robust barrier of charge carrier transfer. The best nano-composite could possess a permittivity of 43@100 Hz (~ 3.3 times of polymer), loss of 0.07@100 Hz (~ 37% of polymer), discharged energy density of 2.23 J/cm3@249 kV/cm (~ 10 times of polymer) and discharged energy efficiency of 54%@249 kV/cm (~ 5 times of polymer). This work might enlighten a facile route to achieve the promising high energy storage composite dielectrics by constructing the layer-by-layer topological structure.