Heterogeneous network constructed by high aspect-ratio Kapok biomass microtube for lightweight and broadband microwave absorbent

Network-structured carbon materials are considered as a practical path to improve impedance matching. While one-dimensional carbon materials with unique large aspect ratio, can highly facilitate the construction of qualified network structures. Inspired by the naturally evolved biomass conduit system, we developed a novel Fe2O3@carbon microtube network ([email protected]) with centimeter-level Kapok microtube as precursor, Fe2O3 nanoparticles as decoration. Notably, [email protected] exhibits excellent absorption bandwidth of 7.09 GHz at ultralow filling ratio of 7.69 wt%, covering 88% of the Ku band. Such excellent EMW performance can be attributed to its unique 1D carbon microtube unit constructed network structure along with heterogeneous interfaces from Fe2O3 nanoparticles cluster. This investigation provides a new prototype for the development of novel EMW absorbing networks by taking advantages of the high aspect ratio one-dimension Kapok microtube unit.