2D filler-reinforced polymer nanocomposite dielectrics for high-k dielectric and energy storage applications

Abstract

Two-dimensional (2D) materials are widely used in various fields because of their excellent thermal, electric and mechanical properties. Polymer nanocomposite dielectrics (PNDs) reinforced with 2D materials exhibit remarkably improved properties, showing great potential in dielectric and energy storage applications. This review summarizes various 2D filler-reinforced PNDs, involving carbon materials, MXenes, oxide ceramics, clays, boron nitride and so on. In general, electrically conductive 2D fillers can endow PNDs a high dielectric constant (εr) at a relatively low filling content by forming percolation systems or microcapacitors and a high dielectric loss, which can be effectively suppressed by surface modification or surface coating. Highly-insulating 2D fillers enhance the breakdown strength (Eb) of PNDs by building up effective conduction barriers, thus increasing their energy storage capability. High-k (εr>3.9) 2D ceramics have potential to enhance the εr and Eb of PNDs simultaneously. Multiphase and multilayer systems also improve the dielectric and energy storage properties of 2D material-reinforced PNDs. Combining the two systems can further enhance these properties of PNDs. Despite great progress, certain challenges still present, which may be solved through close interdisciplinary cooperation.