为扩展石墨烯的应用领域,对磁性功能化石墨烯的电磁波吸收性能进行研究。在氧化石墨与Fe3O4粒子的悬浮液中添加还原剂水合肼,微波辐照反应制备石墨烯/Fe3O4复合物。采用X射线衍射、透射电镜等手段对材料的结构和Fe3O4的分布状态进行了测试表征。采用矢量网络分析仪测定了材料在0.1~18.0 GHz频率范围内的复介电常数和复磁导率。利用Cole-Cole图解释了复合材料的介电特性。利用计算机模拟出不同厚度材料的电磁波衰减性能。结果表明,当石墨烯和Fe3O4粒子以质量比10∶1复合得到的吸波剂材料的匹配厚度在2.0~2.5 mm变化时,反射损耗小于-20 dB的频率覆盖6.5~8.7 GHz。调节Fe3O4粒子的相对含量,复合材料的反射损耗最小可以达到-49.7 dB。复合材料的强吸收特性预示了其作为电磁波吸收材料的潜在应用前景。
For expanding the application field of grahene, electromagnetic wave absorption performance of the magnetic functionalization graphene has been researched in this paper. Graphene/Fe3O4 nanoparticle composites are prepared by microwave irradiating the suspension of graphite oxide and Fe3O4 in the presence of hydrazine hydrate. Transmission electron microscopy and X-ray diffraction are used to characterize the structure and the distribution condition of the composites. Vector network analyzer is used to measure the complex permittivity and complex permeability of the composites in the frequency range of 0.1-18.0 GHz. The permittivity dispersion behaviors are explained based on the Cole-Cole model. The reflection loss curves are calculated using computer simulation technique. Calculation results from the complex permittivity and permeability show that when the mass ratio of graphene to Fe3O4 is 10∶1, reflection losses exceeding -20 dB can be obtained in the frequency range of 6.5-8.7 GHz for absorber thicknesses of 2.0-2.5 mm. By changing the relative content of the Fe3O4 nanoparticles, minimum reflection loss can be obtained at -49.7 dB. Strong absorption properties of the composites indicate its potentially application as electromagnetic wave absorption material.
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