Extended Effective Frequency of Three-Dimensional Graphene with Sustainable Energy Attenuation

A dielectric-magnetic nanocomposite by hybridizing three-dimensional (3D) multiwalled reduced graphene oxide (RGO) and CoFe₂O₄ nanoparticles was synthesized through a simple hydrothermal and freeze-drying route. It is found that the attenuation loss and impedance matching is very important for the microwave absorption property. In addition, the 3D structure could provide more contact sites for microwave attenuation, and the addition of CoFe₂O₄ nanoparticles could promote impedance matching and magnetic loss. The absorption capacity comes from multiinterfaces among 3D CoFe₂O₄/RGO hybrids, dipolar polarization, magnetic loss, and dielectric loss, resulting in the agility of tuning electromagnetic wave absorption. In terms of preparation technology, 3D CoFe₂O₄/RGO hybrids present great potential in electronic facilities with strong microwave response and broadband bandwidth.