▎ 摘　　要

Herein, the composites of MnFe2O4-graphene oxide (MFO@GO) and MnFe2O4-reduced graphene oxide (MFO@rGO) were investigated for their structural and microwave absorption properties. The X-ray photoelectron spectroscopy confirmed the presence of C, O, Fe, and Mn elements, as well as the dominance of Fe3+ over Fe2+ and Mn2+ over Mn3+ oxidation states of Fe and Mn, respectively. The microwave absorption characteristics of composites were discussed in terms of filler loading, dielectric/magnetic loss mechanisms, effective absorption bandwidth (EAB), reflection loss (RL), skin depth, and impedance matching (Smith charts) criteria. The MFO@rGO composites exhibited the best microwave absorption properties (>90% absorption efficiency) over the entire frequency range examined (1-13.5 GHz) among the others. The MFO@rGO composite with 70 wt% filler loading achieved a minimum RL of 38.71 dB at 10.98 GHz and EAB (RL=10 dB) of 3.40 GHz (9.48-12.88 GHz) for a thickness of 1.8 mm within the vicinity of impedance matching criteria.