In this investigation, we successfully synthesized a core–shell nanomaterial featuring ternary Fe₃O₄@mSiO₂@Carbon nanoparticles by utilizing mesoporous silica as the interlayer to disperse small particles of Fe₃O₄, which served as the core of the particles. The ternary nanoparticles Fe₃O₄@mSiO₂@Carbon have demonstrated impressive electromagnetic wave (EW) absorption characteristics, with the most outstanding particle obtained by adding 0.2 g of resorcinol, achieving a minimum reflection loss (RLmin) value of −72.06 dB at an absorber thickness of 4.3 mm. In addition, it has the widest effective absorption bandwidth (EAB), reaching 6.21 GHz at a thickness of 2.7 mm. The radar cross section (RCS) reduction of the composite has been verified by CST simulation in the far field, and the strongest RCS reduction value was up to 38.06 dBm² with a scattering angle of 33°. Our findings indicate that the addition of the mesoporous silica layer benefits the uniform dispersion of the magnetic small particles of Fe₃O₄, improves the impedance matching of the material, and enhances the absorption ability of EW. We posit that our synthesis process can serve as a valuable reference for the development of high-performance, lightweight, and low-density carbon-based EW absorbing nanomaterials.

中文翻译：

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小粒径 Fe3O4 核壳碳基吸收材料的制备研究


在这项研究中，我们利用介孔二氧化硅作为夹层分散作为颗粒核心的 Fe₃O₄ 小颗粒，成功合成了一种具有三元 Fe₃O₄@mSiO₂@Carbon 纳米颗粒的核壳纳米材料。三元纳米颗粒 Fe₃O₄@mSiO₂@Carbon 表现出令人印象深刻的电磁波 （EW） 吸收特性，其中最出色的颗粒是通过添加 0.2 g 间苯二酚获得的，在吸收体厚度为 4.3 mm 时实现了 -72.06 dB 的最小反射损耗 （RLmin） 值。此外，它还具有最宽的有效吸收带宽 （EAB），在 2.7 mm 的厚度下达到 6.21 GHz。在远场通过 CST 仿真验证了复合材料的雷达散射截面 （RCS） 降低，最强的 RCS 降低值高达 38.06 dBm²，散射角为 33°。我们的研究结果表明，介孔二氧化硅层的添加有利于 Fe₃O₄ 磁性小颗粒的均匀分散，改善材料的阻抗匹配，并增强 EW 的吸收能力。我们认为我们的合成过程可以为开发高性能、轻质和低密度的碳基电子战吸收纳米材料提供有价值的参考。