Abstract As the rapid development of electronic devices and wireless communication tools, it is urgent to design and fabricate low-cost, lightweight and effective electromagnetic absorption materials to solve electromagnetic interference of electromagnetic waves. Herein, a facile pre-modification method was employed to design alginate-based Fe@SAC composite absorbers. The core-shell structure could increase the crystallinity of carbon, contributing to a high dielectric loss capacity. The multiple interface polarization effect induced by this structure enhanced the interaction between electromagnetic waves and absorbers, thus accomplished a better wave absorbing effect. Besides, the eddy effect of magnetic particles can also be avoided to realize the impedance matching. Fe@SAC achieved the strongest loss to electromagnetic waves at 9.76 GHz, with the minimum reflection loss up to −41.59 dB. The effective absorption bandwidth reached 2.80 GHz (11.28–14.08 GHz) with a matching thickness merely of 1.5 mm. This efficient, simple and green strategy provides new ideas and development directions for the design of electromagnetic wave absorbers.

中文翻译：

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海藻酸盐衍生的 Fe@SAC 复合吸收剂的简便环保合成，用于高效电磁波衰减

摘要 随着电子设备和无线通信工具的飞速发展，迫切需要设计和制造低成本、轻质、有效的电磁吸收材料来解决电磁波的电磁干扰问题。在此，采用简便的预改性方法设计了基于藻酸盐的 Fe@SAC 复合吸收体。核壳结构可以增加碳的结晶度，有助于提高介电损耗能力。这种结构引起的多界面极化效应增强了电磁波与吸收体之间的相互作用，从而实现了更好的吸波效果。此外，还可以避免磁性粒子的涡流效应，实现阻抗匹配。Fe@SAC 在 9.76 GHz 时实现了最强的电磁波损耗，最小反射损耗高达 −41.59 dB。有效吸收带宽达到 2.80 GHz (11.28-14.08 GHz)，匹配厚度仅为 1.5 mm。这种高效、简单、绿色的策略为电磁波吸收体的设计提供了新的思路和发展方向。