Ultralight 3D cross-linked reinforced graphene@Fe3O4 composite aerogels for electromagnetic wave absorption.

• Fe 3 O 4 nanoparticles were successfully deposited in situ on the pore wall of 3D enhanced graphene aerogel. • The aerogel has strong compression properties. • The aerogel has good microwave absorption performance with the minimum reflection loss -58.13 dB. Graphene aerogels with three-dimensional (3D) hierarchical porous structures have attracted considerable attention as absorptive materials. Here, an enhanced 3D graphene oxide/carbon nanotube/epoxy resin aerogel (GCEA) was used as a template to successfully deposit Fe 3 O 4 nanoparticles on the pore walls through in-situ chemical precipitation, resulting in a 3D composite aerogel absorber (rGCEA@Fe 3 O 4) with both dielectric and magnetic loss properties. The rGCEA@Fe 3 O 4 possesses excellent structural stability, conductive network, and evenly distributed magnetic particles. The rGCEA@Fe 3 O 4 showed excellent electromagnetic wave (EMW) absorption performance, with the minimum reflection loss (RL) reaching -58.13 dB at a frequency of 12.08 GHz and a thickness of 2.5 mm. The effective bandwidth was maximized at 6.64 GHz when the thickness was 2.2 mm. The aerogel prepared in this study can be directly used as encapsulation and absorptive materials for precision instruments. This work provides a new approach for the development of 3D hierarchical absorptive composite materials. Fe 3 O 4 nanoparticles are deposited onto the pore wall of graphene aerogel through in-situ chemical precipitation method. Multiple heterogeneous interfaces are formed among graphene, CNTs and Fe 3 O 4 , leading to the occurrence of both dipole polarization and interface polarization phenomena. The prepared composite aerogel exhibits excellent dielectric and magnetic loss properties, demonstrating outstanding absorption performance. [Display omitted] [ABSTRACT FROM AUTHOR]