石墨烯-Fe@Fe_3O_4纳米复合材料的制备及其电磁性能研究

Synthesis and Characteristics of Graphene-Fe@Fe_3O_4 Nano-Composites Materials

采用改进Hummers法制备氧化石墨,通过高温热膨胀剥离氧化石墨获得多层石墨烯,最后由羰基铁热分解法原位制备多层石墨烯-Fe@Fe3O4纳米复合材料。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、振动样品磁强计(VSM)以及矢量网络分析仪等对该复合材料的结构、形貌、电磁参数等进行了表征和测试。结果表明,石墨烯片层上附着了尺寸小于50 nm的球形Fe@Fe3O4颗粒;反射率损耗(RL)计算结果表明:以金属为衬底,当复合材料厚度为1.5 mm时,在10～16GHz范围内反射损耗均在-10 dB以下;当厚度为3 mm时,材料的反射损耗在4.3 GHz处达最大值,约为-25 dB。

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 muhilayer 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 nanoparticles 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 10-16 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.