Iron-based nanotubes are promising candidates for high performance electromagnetic wave absorbing fillers due to their high aspect ratio, light weight, high axial permeability and high saturation magnetization. Furthermore, the introduction of carbon can improve dielectric loss and block the agglomeration of iron nanotubes. Here, Fe@C composite nanotubes were prepared by introducing carbon onto the surface of precursor α-FeOOH’ fibers followed by hydrogen-thermal annealing. We find that Fe@C composite nanotubes retain the one-dimensional nanostructure of the precursor throughout the annealing. The well-developed lattice and nanostructure of Fe@C nanotubes endow high saturation magnetization, high anisotropy, suppressed eddy current effect and cross-particle exchange coupling as well, and thus contribute to an enhanced permeability. Coatings with Fe@C as fillers achieve a reflection loss of up to −69.34 dB at 3.37 GHz at the matching thickness of 3.97 mm. The Fe@C composite nanotubes developed here are a promising candidate for high performance electromagnetic wave absorbing fillers.

铁基纳米管因其高长径比、轻质、高轴向磁导率和高饱和磁化强度而成为高性能电磁波吸收填料的有希望的候选者。此外，碳的引入可以改善介电损耗并阻止铁纳米管的团聚。在此，通过将碳引入到前驱体 α-FeO​​OH' 纤维的表面，然后进行氢热退火，制备了 Fe@C 复合纳米管。我们发现 Fe@C 复合纳米管在整个退火过程中保留了前驱体的一维纳米结构。Fe@C纳米管发达的晶格和纳米结构赋予高饱和磁化强度、高各向异性、抑制涡流效应和跨颗粒交换耦合，从而有助于提高磁导率。以 Fe@C 作为填料的涂层在 3.37 GHz 的匹配厚度为 3.97 mm 时实现了高达 -69.34 dB 的反射损耗。这里开发的 Fe@C 复合纳米管是高性能电磁波吸收填料的有前途的候选者。