The lightweight, strong absorption, non-resin, and high chemical and thermal stability of electromagnetic wave absorption materials used in space vehicles are required in the harsh space environments. Herein, a light weight and effective microwave-absorbing material is constructed by synthesizing carbide-modified reduced graphene oxide (rGO) aerogels, gradient design and carbonization. The as-prepared aerogel material consists of molybdenum carbide (MC) and rGO, and displays hollow structures with multi-wall rGO layers. The MC structure in the MC/rGO aerogel is regulated by controlling the amount of Mo source, and the dual gradient structure composed of MC/rGOmaterial is designed and optimized by CST Microwave Studio. Compared with MC/rGO aerogel, the dual-gradient MC/rGO (DG-MC/rGO) aerogel exhibits superior impedance matching and significantly enhanced microwave absorption performance. The minimum reflection loss (-62.4 dB) is reduced by 64.6%, and the effective absorption bandwidth (5.7 GHz) is increased by over 35.7% at a thickness of 2.2 mm. The remarkable improvement of microwave absorption is attributed to the synergy effect of well-dispersed molybdenum carbide nanoparticles and the components/structures gradients of DG-MC/rGO material. This novel lightweight material has promising applications in electromagnetic wave absorption fields.

中文翻译：

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双梯度 Mo2C 修饰的 rGO 气凝胶，用于增强电磁波吸收


在恶劣的太空环境中，需要航天器中使用的电磁波吸收材料具有轻质、强吸收、非树脂以及高化学和热稳定性。在此，通过合成碳化物改性的还原氧化石墨烯 （rGO） 气凝胶、梯度设计和碳化构建了一种重量轻且有效的微波吸收材料。所制备的气凝胶材料由碳化钼 （MC） 和 rGO 组成，并显示出具有多壁 rGO 层的中空结构。MC/rGO 气凝胶中的 MC 结构通过控制 Mo 源的量进行调节，由 MC/rGO材料组成的双梯度结构由 CST Microwave Studio 设计和优化。与 MC/rGO 气凝胶相比，双梯度 MC / RGO （DG-MC/rGO） 气凝胶表现出优异的阻抗匹配和显著增强的微波吸收性能。最小反射损耗 （-62.4dB） 降低了 64.6%，在 2.2mm 的厚度下，有效吸收带宽 （5.7GHz） 增加了 35.7% 以上。微波吸收的显着改善归因于分散良好的碳化钼纳米颗粒与 DG-MC/rGO 材料的组分/结构梯度的协同效应。这种新型轻质材料在电磁波吸收领域具有广阔的应用前景。