Biomass carbon has been widely studied as an electromagnetic wave-absorbing material in recent years due to its wide range of material sources, natural porous structure, and other advantages. Herein, a series of magnetic lignin-based carbon composites have been prepared as electromagnetic wave absorbers using carboxylation lignin as an organic ligand and Fe, Co as a metal ion. The bimetallic to coordinate combination with carboxylation lignin improved the agglomeration phenomenon, optimized mesoporous structure, and the pore distribution of the material compared to monometallic. This lignin-based FeCo@C had an abundant interfacial, mesoporous structure, dielectric, and magnetic loss capability. When the ratio of Fe and Co was 1:1, the reflection loss value of −48.5 dB at 12.3 GHz, and the effective absorption bandwidth achieved 4.52 GHz with a thickness of 2.5 mm. In short, this work provided a new direction for the preparation of renewable and high-performance lignin-based electromagnetic wave absorber materials.

中文翻译：

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一种可调谐结构的木质素衍生碳基磁性复合材料，用于有效吸收电磁波

生物质碳因其材料来源广泛、天然多孔结构等优点，近年来作为电磁波吸收材料得到了广泛的研究。本文以羧化木质素为有机配体，Fe、Co为金属离子，制备了一系列磁性木质素基碳复合材料作为电磁波吸收剂。与单金属相比，双金属与羧化木质素的配位结合改善了团聚现象，优化了材料的介孔结构和孔分布。这种木质素基 FeCo@C 具有丰富的界面、介孔结构、介电和磁损耗能力。当Fe和Co的比例为1:1时，在12.3 GHz时反射损耗值为-48.5 dB，有效吸收带宽在2.5 mm厚度下达到4.52 GHz。总之，这项工作为可再生、高性能木质素基电磁波吸收材料的制备提供了新的方向。