Oraby Hussein, Tantawy Hesham Ramzy, Correa-Duarte Miguel A, Darwish Mohammad, Elsaidy Amir, Naeem Ibrahim, Senna Magdy H
Department of Chemical Engineering, Military Technical College, Cairo 1111, Egypt.
Centro de Investigacions Biomedicas (CINBIO), Universidade de Vigo, 36310 Vigo, Spain.
Nanomaterials (Basel). 2022 Aug 16;12(16):2805. doi: 10.3390/nano12162805.
Electromagnetic interference (EMI) has been recognized as a new sort of pollution and can be considered as the direct interference of electromagnetic waves among electronic equipment that frequently affects their typical efficiency. As a result, shielding the electronics from this interfering radiation has been addressed as critical issue of great interest. In this study, different hybrid nanocomposites consisting of magnetite nanoparticles (FeO) and reduced graphene oxide (rGO) as (conductive/magnetic) fillers, taking into account different rGO mass ratios, were synthesized and characterized by XRD, Raman spectroscopy, TEM and their magnetic properties were assessed via VSM. The acquired fillers were encapsulated in the polyurethane foam matrix with different loading percentages (wt%) to evaluate their role in EMI shielding. Moreover, their structure, morphology, and thermal stability were investigated by SEM, FTIR, and TGA, respectively. In addition, the impact of filler loading on their final mechanical properties was determined. The obtained results revealed that the FeO@rGO composites displayed superparamagnetic behavior and acceptable electrical conductivity value. The performance assessment of the conducting FeO@rGO/PU composite foams in EMI shielding efficiency (SE) was investigated at the X-band (8-12) GHz, and interestingly, an optimized value of SE -33 dBw was achieved with FeO@rGO at a 80:20 wt% ratio and 35 wt% filler loading in the final effective PU matrix. Thus, this study sheds light on a novel optimization strategy for electromagnetic shielding, taking into account conducting new materials with variable filler loading, composition ratio, and mechanical properties in such a way as to open the door for achieving a remarkable SE.
电磁干扰（EMI）已被公认为一种新型污染，可被视为电子设备之间电磁波的直接干扰，这种干扰经常影响其正常效率。因此，屏蔽电子设备免受这种干扰辐射已成为备受关注的关键问题。在本研究中，合成了不同的混合纳米复合材料，其由磁铁矿纳米颗粒（FeO）和还原氧化石墨烯（rGO）作为（导电/磁性）填料，并考虑了不同的rGO质量比，通过X射线衍射（XRD）、拉曼光谱、透射电子显微镜（TEM）对其进行了表征，并通过振动样品磁强计（VSM）评估了它们的磁性。将获得的填料以不同的负载百分比（wt%）封装在聚氨酯泡沫基质中，以评估它们在电磁干扰屏蔽中的作用。此外，分别通过扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和热重分析（TGA）研究了它们的结构、形态和热稳定性。此外，还确定了填料负载对其最终机械性能的影响。所得结果表明，FeO@rGO复合材料表现出超顺磁性行为和可接受的电导率值。在X波段（8 - 12）GHz下研究了导电FeO@rGO/PU复合泡沫在电磁干扰屏蔽效率（SE）方面的性能评估，有趣的是，在最终有效的PU基质中，当FeO@rGO的质量比为80:20 wt%且填料负载为35 wt%时，实现了SE为 - 33 dBw的优化值。因此，本研究揭示了一种新型的电磁屏蔽优化策略，并考虑了具有可变填料负载、组成比例和机械性能的新型导电材料，从而为实现显著的SE打开了大门。
