Fibrous Composites with Double-Continuous Conductive Network for Strong Low-Frequency Microwave Absorption

Low-frequency electromagnetic absorption is an important issue that has troubled microwave absorbing materials for years. To solve these challenges, fibrous composites with a double-continuous conductive network sustainably derived from natural raw cotton fabrics, Fe₃O₄ nanoparticles (NPs), and polypyrrole (PPy) films were fabricated from bottom to top. The first level of magnetic fibrous structure is from the inherent raw cotton fabrics and Fe₃O₄ NPs, while the second level of the double-continuous conductive network is produced by the in situ polymerization of pyrrole monomers and FeCl₃. The effect of fibrous pores and double-continuous conductive network endows the fibrous composites with excellent microwave absorption performance. The fibrous composites not only exhibit amazing reflection losses of -67.6 dB at 4.0 GHz and -54 dB at 3.5 GHz respectively, but also exhibit as being lightweight. The developed materials are promising for applications in high-performance stealth aircraft and electromagnetic pollution.