Magnetic poly(ionic liquid)/graphene oxide/Fe3O4 composites with multiple loss mechanisms for microwave absorbing

Microwave-absorbing materials are very important to reduce electromagnetic interference and pollution. Combining multi-component materials with multiple loss mechanisms is a practical strategy for enhancing microwave absorption performance. In this work, we synthesize a magnetic poly(ionic liquid) (PVim[FeCl₄]) with crosslinkable groups and prepare PVim[FeCl₄]/graphene oxide (GO)/Fe₃O₄ composites by incorporating GO and Fe₃O₄ to enhance the microwave absorption property of the composites. The synergistic effect of GO and Fe₃O₄ is studied at different feeding ratios, the PVim[FeCl₄]/10%GO/20%Fe₃O₄ composite shows better microwave absorption performance, with a minimum reflection loss (RL_min) of −49.54 dB at 17.31 GHz and 7.1 mm thickness, along with an effective absorption bandwidth (EAB) of 2.52 GHz. This enhancement can be attributed to the quarter-wavelength matching model, well-matched characteristic impedance, and multiple loss mechanisms originating from PVim[FeCl₄], GO, and Fe₃O₄. The magnetic poly(ionic liquid) composites show promising prospects in microwave absorbing materials.