Abstract We present the design, synthesis, and characterization of the graphene oxide (GO)-SiO2/Fe3O4 nanocomposite as well as its applications for microwave absorption. The GO-SiO2/Fe3O4 nanocomposites were synthesized with three different compositions having mass ratios (1:1), (1:2), and (1:3). Graphene oxide was synthesized by the modified Hummers’ method, while GO-SiO2 was hydrothermally synthesized, and GO-SiO2/Fe3O4 nanocomposites were obtained in a single pot process using different ratios of the mass of magnetite. Various characterization techniques were used to examine carefully the samples. SEM and TEM images show the creation of SiO2 and Fe3O4 nanoparticles on GO layers, which are confirmed by XRD. Next, we studied in detail the microwave absorption properties of all GO-SiO2/Fe3O4 composites. We have verified that GO-SiO2/Fe3O4 (1:3) with a high magnetic saturation of ∼70.5 emu g−1 and a corresponding layer thickness of 2 mm has excellent microwave absorption with a minimum reflection loss of −72.79 dB at 15.87 GHz and an effective absorption bandwidth (less than −10 dB) equal to 2.43 GHz (14.49–16.92 GHz). Besides, the maximum effective bandwidth reaches 7.54 GHz (10.46–18.0 GHz) and 7.39 GHz (10.61–18.0) for thicknesses of 3.2 mm and 3.6 mm in samples (1:2) and (1:1), respectively.

中文翻译：

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通过有效的设计和优化的成分对 GO-SiO2/Fe3O4 的显着微波吸收

摘要 我们介绍了氧化石墨烯 (GO)-SiO2/Fe3O4 纳米复合材料的设计、合成和表征及其在微波吸收方面的应用。GO-SiO2/Fe3O4 纳米复合材料由三种不同的组成，质量比为 (1:1)、(1:2) 和 (1:3)。氧化石墨烯采用改进的 Hummers 法合成，GO-SiO2 采用水热法合成，采用不同质量比的磁铁矿在单锅法中得到 GO-SiO2/Fe3O4 纳米复合材料。使用各种表征技术仔细检查样品。SEM 和 TEM 图像显示在 GO 层上产生了 SiO2 和 Fe3O4 纳米颗粒，这通过 XRD 得到证实。接下来，我们详细研究了所有 GO-SiO2/Fe3O4 复合材料的微波吸收性能。我们已经验证了 GO-SiO2/Fe3O4 (1: 3) 具有~70.5 emu g-1 的高磁饱和度和 2 mm 的相应层厚具有出色的微波吸收性，在 15.87 GHz 时具有 -72.79 dB 的最小反射损耗和有效吸收带宽（小于 -10 dB）等于 2.43 GHz (14.49–16.92 GHz)。此外，对于厚度为 3.2 mm 和 3.6 mm 的样品 (1:2) 和 (1:1)，最大有效带宽分别达到 7.54 GHz (10.46–18.0 GHz) 和 7.39 GHz (10.61–18.0)。