Kapok fibers-derived carbon microtubes as efficient electromagnetic wave absorption materials

Abstract

The superior electromagnetic wave absorption materials have the characteristics of thin matching thickness, low density, wide absorption bandwidth and strong absorption intensity, which can effectively deal with electromagnetic pollution. With the further research, biomass-derived carbon has received great focus due to abundant biological reserves and unique natural structure. Herein, we put forward an excellent electromagnetic wave absorption material, carbon microtubes (CMTs) with a one-dimensional hollow tubular structure, which derived from kapok fibers (KFs) via a facile annealing method. The result shows that the effective absorption bandwidth (EAB) of CMTs is 6.78 GHz under 900 °C annealing conditions. Especially, the filling ratio is just 3 wt% and the matching thickness is 2.06 mm. The superior electromagnetic wave absorption properties of CMTs can be related to its microstructural characteristics. This one-dimensional tubular structure has a large specific surface area increasing the interaction area between the material and electromagnetic waves, while the hollow tube cavity can make the incident electromagnetic waves for multi-ply scattering and reflection strengthening the dissipation capability of the material. This work offers a convenient way to produce effective electromagnetic wave absorption materials with low cost and eco-friendly environment.