Abstract Highly efficient microwave absorption materials with tunable electromagnetic properties have been attracting extensive attention. However, it still remains a challenge to fabricate the chiral materials decorated with core-shell structured magnetic-particles for excellent microwave absorption performance. Herein, a novel composite of helical carbon nanocoils (CNCs) and Fe3O4@C core-shell structures are synthesized, for the first time, via sequential processes of chemical vapor deposition (CVD) technique and hydrothermal reactions. By controlling the reaction temperature and time in CVD process, the composites with different morphologies and multilevel heterostructural interfaces are obtained. The minimum reflection loss of the CNC/Fe3O4@C composite reaches −47.5 dB at 13.4 GHz with a thickness of only 1.7 mm. Meanwhile, the composite also exhibits an effective frequency range (≤−10 dB) of as wide as 5.03 GHz at a thickness of only 1.5 mm. Our designs not only provide a scalable way for preparing a kind of novel and robust absorber but also offer inspirations for construction of a kind of composite consisting of chiral and core-shell structured materials.

中文翻译：

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用于高效电磁波吸收的分层核-壳 Fe3O4@C 纳米颗粒-螺旋碳纳米线圈混合复合材料的原位构建

摘要 具有可调电磁特性的高效吸波材料受到广泛关注。然而，制造具有核壳结构磁性颗粒装饰的手性材料以获得优异的微波吸收性能仍然是一个挑战。在此，首次通过化学气相沉积 (CVD) 技术和水热反应的顺序过程合成了螺旋碳纳米线圈 (CNCs) 和 Fe3O4@C 核壳结构的新型复合材料。通过控制CVD过程中的反应温度和时间，获得了不同形貌和多级异质结构界面的复合材料。CNC/Fe3O4@C 复合材料的最小反射损耗在 13.4 GHz 时达到 -47.5 dB，厚度仅为 1.7 mm。同时，该复合材料在厚度仅为 1.5 毫米的情况下还表现出高达 5.03 GHz 的有效频率范围 (≤-10 dB)。我们的设计不仅为制备一种新型且坚固的吸收体提供了一种可扩展的方法，而且还为构建一种由手性和核壳结构材料组成的复合材料提供了灵感。