Graphene Composites with Dual Functionality: Electromagnetic Shielding and Thermal Management

TL;DR

This paper presents epoxy-based composites with few-layer graphene that achieve high electromagnetic shielding and thermal conductivity, offering dual functionality for advanced thermal and electromagnetic management in lightweight systems.

Contribution

It introduces a novel dual-functional graphene composite with optimized filler characteristics for simultaneous electromagnetic shielding and thermal conduction.

Findings

Electromagnetic shielding effectiveness of ~45 dB in X-band.

Thermal conductivity increased to 8 W/mK, 35 times higher than base material.

Graphene composites block electromagnetic energy below percolation threshold, remaining insulating.

Abstract

We report on the synthesis and characterization of the epoxy-based composites with the few-layer graphene fillers, which are capable of the duel functional applications. It was found that composites with the certain types of few-layer graphene fillers reveal an efficient total electromagnetic interference shielding, SE~45 dB, in the important X-band frequency range, f=8.2 GHz - 12.4 GHz, while simultaneously providing the high thermal conductivity, K = 8 W/mK, which is a factor of x35 larger than that of the base matrix material. The efficiency of the dual functional application depends on the filler characteristics: thickness, lateral dimensions, aspect ratio and concentration. Graphene loading fractions above the percolation threshold allow for strong enhancement of both the electromagnetic interference shielding and heat conduction properties. Interestingly, graphene composites can block the electromagnetic energy even below the percolation threshold, remaining electrically insulating, which is an important feature for some types of thermal interface materials. The dual functionality of the graphene composites can substantially improve the electromagnetic shielding and thermal management of the airborne systems while simultaneously reducing their weight and cost.