Great improvements for wireless techniques and electronic devices require effective electromagnetic (EM) absorbing materials to solve EM radiation and interference problems. Herein, cobalt sulfide/reduced graphene oxide (CoS/rGO) nanocomposites were prepared through a simple one-pot hydrothermal method. The microwave absorption performance of CoS/rGO nanocomposites with different rGO proportions was systematically investigated. The CoS/rGO 1:1 nanocomposite achieves the reflection loss (RL) value of −37.3 dB at 8.6 GHz. The effective RL values (<−10 dB) of the CoS/rGO 1:1 nanocomposite are obtained in the frequency of 3.4–18 GHz while the thickness varies from 2.0 mm to 5.0 mm. Additionally, the simulated radar cross section results indicate that the CoS/rGO nanocomposites can efficiently suppress the strong EM scattering of metal plate in different incident degrees. These achievements demonstrate that the CoS/rGO nanocomposites can be used as high-performance microwave absorbing materials.

中文翻译：

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微波吸收性能可调的还原氧化石墨烯包裹硫化钴纳米粒子的制备

无线技术和电子设备的巨大改进需要有效的电磁 (EM) 吸收材料来解决电磁辐射和干扰问题。在此，通过简单的一锅水热法制备了硫化钴/还原氧化石墨烯（CoS/rGO）纳米复合材料。系统地研究了具有不同 rGO 比例的 CoS/rGO 纳米复合材料的微波吸收性能。CoS/rGO 1:1 纳米复合材料在 8.6 GHz 下实现了 -37.3 dB 的反射损耗 (RL) 值。CoS/rGO 1:1 纳米复合材料的有效 RL 值 (<-10 dB) 在 3.4-18 GHz 的频率下获得，而厚度从 2.0 毫米到 5.0 毫米不等。此外，模拟雷达截面结果表明 CoS/rGO 纳米复合材料可以有效抑制金属板在不同入射程度下的强电磁散射。这些成果表明 CoS/rGO 纳米复合材料可用作高性能微波吸收材料。