Cu/Fe3O4 heterogeneous nanospheres anchoring defect-rich graphene for effectively enhanced multi-band electromagnetic absorption

Nowadays, the practical application of electromagnetic absorbing materials required lightweight, high efficiency and especially broadband. Wherein, graphene-based electromagnetic absorbing materials had received extensive attention. The conventional design was to introduce magnetic particles onto graphene, but often lead to narrow bandwidth, hard to regulate, due to the lack of intrinsic coupling between magnetic particles and dielectric graphene. In principle, defect engineering could induce intrinsic ferromagnetism into graphene while increasing dielectric polarization loss, could be an effective means of expanding and regulating electromagnetic absorbing bands. Thus, in this paper, Cu/Fe3O4 heterogeneous nanospheres was constructed onsite defect-rich graphene to realize broadband electromagnetic absorbing modulation. The optimal RL value of Cu/Fe3O4/GE could reach -45.5 dB with obvious multi-band absorption, which was mainly attributed to the synergistic enhancement of defect-induced polarization loss, multiple interfacial polarization loss, as well as collaborative multipath magnetic loss. This work provides reference way for lightweight multi-band electromagnetic absorbing materials design.