Abstract The increasing excess electromagnetic wave (EMW) radiations induce a serious pollution problem. The social requests urgently for EMW absorbing materials. Herein, as-prepared magnetic carbon foam (MCF) adsorbed RhB from the dye pollutant solutions. The used adsorbent was heat-treated at high temperature. Then, magnetic particle-decorated N-doped carbon foams (N-MCFs) were fabricated. N-doping content is determined by mass ratio of adsorbed RhB vs MCF. Excellent EMW absorption performance is achieved by optimizing impedance matching of N-MCFs. N-MCF-2 with a loading rate of 15% exhibits a lowest R L m i n value of −60.46 dB with a T m value as thin as only 1.70 mm. The corresponding effective bandwidth is 14.29 GHz and 13.79 GHz for −10 dB and −20 dB, covering the whole C band, X band and Ku band. For the absorbers with higher conductivities, the corresponding EMW absorption capacity can be further improved by reducing the loading rate. The distorted skeletons caused by N-doping induce the graphite lattice distortion and local density change of the carbon atomic state, significantly contributing to the magnetic moment. The enhanced dielectric loss by both defect polarization and dipole polarization effects, as well as the activated complex permeability by α-Fe/Fe3C/Fe2O3 composites decoration, are beneficial to EMW absorption.

中文翻译：

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使用染料吸附剂衍生的具有增强电磁波吸收性能的 N 掺杂磁性碳泡沫

摘要 不断增加的过量电磁波 (EMW) 辐射引发了严重的污染问题。社会对电磁波吸收材料的需求迫切。在此，所制备的磁性碳泡沫 (MCF) 从染料污染物溶液中吸附了 RhB。用过的吸附剂经过高温热处理。然后，制造了磁性颗粒装饰的 N 掺杂碳泡沫（N-MCF）。N-掺杂含量由吸附的 RhB 与 MCF 的质量比决定。通过优化 N-MCF 的阻抗匹配，实现了出色的 EMW 吸收性能。负载率为 15% 的 N-MCF-2 表现出最低的 RL 最小值 -60.46 dB，T m 值仅薄至 1.70 mm。对应的有效带宽为-10 dB和-20 dB的14.29 GHz和13.79 GHz，覆盖了整个C频段、X频段和Ku频段。对于电导率较高的吸收体，可以通过降低加载速率进一步提高相应的 EMW 吸收能力。由 N 掺杂引起的扭曲骨架引起石墨晶格畸变和碳原子状态的局部密度变化，对磁矩有显着贡献。缺陷极化和偶极极化效应增强的介电损耗，以及 α-Fe/Fe3C/Fe2O3 复合材料装饰激活的复合磁导率，有利于 EMW 吸收。