Interfacially Engineered Sandwich‐Like rGO/Carbon Microspheres/rGO Composite as an Efficient and Durable Microwave Absorber

Graphene-based composites offer immense potential for overcoming the challenges related to the performance, functionality, and durability in microwave absorption. In this study, a sandwich-like graphene-based composite is successfully fabricated by an interfacial engineering of amorphous carbon microspheres (ACMs) and reduced graphene oxide (rGO), with a structure of rGO/ACMs/rGO. The as-prepared rGO/ACMs/rGO composite presents comparable/superior reflection loss characteristics in the frequency range of 2.0-18.0 GHz to previous composites of graphene and high-density magnetic particles. Electromagnetic parameters and simulation results reveal that well-matched characteristic impedance and proper dielectric loss, as well as multiple reflections and interfacial polarizations derived from the unique microstructure should account for the enhanced microwave absorption of rGO/ACMs/rGO. More importantly, rGO/ACMs/rGO exhibits durable performance after being treated at high temperature for a long time. This work provides a new idea for exploring high-performance and durable microwave absorbers of graphene-based materials.