▎ 摘　　要

The preparation of graphite oxide (GO) was carried out by modified Hummer's method. The multilayer graphene was obtained by thermally exfoliation of GO. Subsequently, the in situ information of multilayer graphene-Fe@Fe3O4 nano-composite was carried out through the heated decomposition of carbonyl iron. The microstructure, morphology, and electromagnetic parameters of the graphene-Fe@Fe3O4 nano-composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electronic microscopy(TEM), vibrating sample magnetometer (VSM) and vector network analyzer. The results show that the sphere shaped Fe@Fe3O4 nanoparticies with diameter of less than 50 nm were attached to the graphene layers. Calculated reflection loss (RL) baked with the perfect metal indicates that the composite has a less than -10 dB reflection loss in the frequency range of 10 similar to 16 GHz under the thickness of 1.5 mm, and reaches peak value of -25 dB reflection loss at 4.3 GHz when the thickness is 3 mm.