Enhancing electromagnetic wave absorption performance of one-dimensional C@Co/N-doped C@PPy composite fibers

Electrospinning is one of the attractive technologies for fabrication carbon-based fibers due to its high efficiency, component controllability and functionalities. Here, a multi-step strategy was used for the efficient synthesis of one-dimensional (1D) MOF-derived C@Co/N-doped carbon@polypyrrole (C@Co/NC@PPy) composite fibers. The composite fibers synthesized by introducing the electrospinning method possessed unique structural anisotropy and multiple absorption mechanisms. The electromagnetic parameters, the absorption performance and the internal mechanisms of samples were thoroughly illustrated. By adjusting the filler loadings of samples, the electromagnetic wave (EMW) absorption could be optimized. The C@Co/NC@PPy with 35 wt% filler loading showed the optimal performance. Impressively, with a thickness of merely 1.65 mm, the C@Co/NC@PPy composite fibers delivered high performance with the minimum reflection loss (RLmin) of -72.14 dB. Correspondingly, the maximum effective absorption bandwidth (EABmax) could reach 5.6 GHz with the thickness of 1.88 mm. Furthermore, the 35 wt% loading C@Co/NC@PPy composite fibers could reach 14.28 GHz (89.25% of 2-18 GHz) effective absorption, showing the ultrawide absorption. Those positive results forcefully verified that the 1D MOF-derived C@Co/NC@PPy composites showed great potential and superiority as EMW absorption material.