It is well known that the surface architecture of an absorber has a significant effect on the final electromagnetic (EM) wave attenuation behavior. Herein, a series of nanoporous carbon media with different surface morphologies, including a honeycomb-like structure, three dimension (3D) interrelated network, and irregular lump shape, were obtained by a facile one-step strategy employing the green biomass of wheat flour as the precursor. By optimizing the surface architecture, it is demonstrated that the elaborate 3D interrelated skeleton makes a crucial contribution on the eventual EM absorption performance. At the identical low filler content of only 8 wt %, the nanoporous carbon media with a 3D interrelated skeleton shows the minmium reflection loss (RL_min) of −51 dB, almost 9 times higher than that of the other two nanoporous carbon media with honeycomb-like structures and irregular lump shapes. The corresponding effective frequency bandwidth (f_e, RL exceeding −10 dB) of 4.8 GHz was achieved at a thin thickness of 1.8 mm. Moreover, when slightly changing the mass percentage to 9 wt % in the paraffin matrix, the broad f_e region of 6 GHz could cover the whole Ku band. This work provides a facile, sustainable, and low-cost approach for developing ultralight and highly efficient absorption media by means of a renewable biomass as te source, and the derived 3D carbon skeleton displays a great potential for dealing with EM interference.

中文翻译：

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通过改变纳米多孔碳的表面形态来实现面粉的可持续超轻电磁吸收剂

众所周知，吸收体的表面结构对最终的电磁波（EM）衰减行为有重大影响。本文以小麦粉绿色生物质为原料，采用简便的一步法，获得了一系列蜂窝状结构，三维（3D）关联网络，团块形状不规则的纳米多孔碳介质。前体。通过优化表面结构，可以证明精心设计的3D相互关联的骨架对最终的EM吸收性能做出了至关重要的贡献。在仅8 wt％的相同低填料含量下，具有3D关联骨架的纳米多孔碳介质显示出最小的反射损耗（RL _min）-51 dB，几乎是其他两种蜂窝状结构和不规则块状纳米孔碳介质的9倍。在1.8mm的薄厚度处获得了4.8GHz的相应的有效频率带宽（f _e，RL超过-10 dB）。此外，当将石蜡基质中的质量百分比略微更改为9 wt％时，6 GHz的宽f _e区域可以覆盖整个Ku频段。这项工作为通过利用可再生生物质作为来源开发超轻和高效吸收介质提供了一种简便，可持续且低成本的方法，并且衍生的3D碳骨架显示出了应对EM干扰的巨大潜力。