膨胀石墨/聚苯胺/Fe_3O_4复合材料的制备及吸波性能

采用原位聚合方法制备了膨胀石墨/聚苯胺(EG/PANI)复合材料,将Fe_3O_4负载于EG/PANI表面,得到具有电磁吸收性能的EG/PANI/Fe_3O_4复合材料.通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)、傅里叶变换红外光谱仪(FTIR)及矢量网络分析仪(VNA)等对复合材料的形貌、成分和吸波性能进行了研究.吸波性能分析结果表明,当掺杂浓度为0.05 mol/L,匹配厚度d=2 mm时,样品的最小反射损耗(RLmin)在8.64 GHz处达到-37 dB.随着掺杂浓度的增加,最小反射损耗峰向低频移动,对应的匹配厚度逐渐变厚.材料的介电弛豫极化、涡流损耗及λ/4模型的干涉相消现象出现的双峰,使EG/PANI/Fe_3O_4复合材料在电磁波吸收领域有一定的应用前景.

Fabrication and Microwave Absorption Performances of EG-PANI-Fe3O4 Composites

Expanded graphite / polyaniline(EG/ PANI) composites were synthesized by in-situ polymerization, and EG/ PANI/ Fe3O4 composites were obtained by adsorbing Fe3 O4 nanoparticles on the surface of EG/ PANI composites. The surface morphologies, phase structures and microwave absorption properties were characterized by scanning electron microscopy( SEM), X-ray diffraction( XRD), Fourier transform infrared (FTIR), and vector network analyzer(VNA). The results showed that when the HCl concentration was 0. 05 mol/ L, the RLmin reached -37 dB at 8. 64 GHz with the thickness of d = 2 mm. With the increase of doping concentration, the minimum reflection loss peak moved to low frequency, and the matching thickness became thicker. The dielectric relaxation polarization, eddy current loss and interference cancellation phenomenon ofλ / 4 model played the important role in the process of absorption. The double peaks made EG/ PANI/ Fe3O4 composites possible in the microwave absorption.