Flexible reduced graphene oxide@Fe₃O₄/silicone rubber composites for enhanced microwave absorption

Reduced graphene oxide@Fe₃O₄ (rGO@Fe₃O₄) nanocomposites were developed via a facile thermal decomposition method, which were subsequently incorporated into silicone rubber (SR) matrix to fabricate flexible rGO@Fe₃O₄/SR composites through mold pressing, followed by curing. The in situ grown Fe₃O₄ nanoparticles on the rGO sheets endowed the rGO@Fe₃O₄/SR composites with magnetic properties and provided heterogeneous interface, which led to better impedance matching, enhanced magnetic loss and interfacial polarization loss. Under synergistic effect between dielectric loss and magnetic loss, the rGO@Fe₃O₄/SR composites exhibited high microwave absorption efficiency and wide absorption bandwidth. The minimum reflection loss value reached −59.4 dB at the frequency of 8.0 GHz, and the absorption bandwidth was 4.2 GHz at a thin layer of 1.2 mm. The rGO@Fe₃O₄/SR composites also showed excellent thermal conduction ability, which enabled fast dissipation of the heat generated by absorbing the microwave energy. The features of strong absorption, broad absorption bandwidth, high flexibility, small thickness, and excellent heat dissipation make the rGO@Fe₃O₄/SR composites promising microwave absorption candidates for aerospace and flexible electronics.