Self-assembly of graphene foam anchored with magnetic Fe2O3 nanocrystals for high efficient electromagnetic wave absorption

Abstract

Three-dimensional (3D) graphene based materials have many advantages including low density, large specific surface area, high electrical conductivity, abundance of pores and good mechanical compressibility, which make them considered as potential candidate for electromagnetic wave (EMW) absorption materials. In this study, the 3D graphene foam anchored with magnetic Fe₂O₃ nanocrystals using diethylene glycol as solvent (3D-DEG-rGO@Fe₂O₃) were prepared by solvothermal method, synchronously realizing the self-assembly of 3D graphene and in-situ reduction of magnetic Fe₂O₃ nanoparticles without any reducing agent. The 3D-DEG-rGO@Fe₂O₃ demonstrates excellent microwave absorption due to good impedance matching and synergistic electromagnetic loss mechanisms as well as porous network structure. The minimum reflection loss (RL_min) is − 63.86 dB at 12.47 GHz with a thin thickness of only 2.28 mm, and the effective frequency bandwidth with the RL values less than − 10 dB is 5.53 GHz in the range of 12.47–18 GHz. The 3D-DEG-rGO@Fe₂O₃ foam with extremely low bulk density, excellent EMW absorption ability and good compression recovery, can be attractive candidate materials for EMW absorption applications.