Facile Strategy To Prepare Light-Weight PVA Membrane Based on Schiff Base Derivatives and MWCNTs for Electromagnetic Wave Absorption

The carbon-nanotube-doped Schiff bases (CDSBs) and their iron complexes (CDSI) were synthesized by the in situ polymerization and coordination reaction. The phase structure and morphology of the samples were investigated by X-ray diffraction analysis and field-emission scanning electron microscopy. In particular, it can be found that the diamagnetic substance CDSF turns into paramagnetic CDSI after doping Fe3+. Furthermore, the eminent electrical conductivity and microwave electromagnetic loss behavior of CDSI shed light on organic–metal ion complexes (OMICs) as a promising lightweight absorbent. The feasibility of this strategy was demonstrated by the successful fabrication of the CDSI/MWCNTs/PVA composites membrane. The reflection loss (RL) of the electromagnetic wave arrives at the lowest value −18.6 dB at 10.32 GHz, and the effective bandwidth (RL below −10 dB) could reach 5.8 GHz (8.1 to 13.04 GHz) with the thickness of 0.54 mm and the surface density of 0.44 kg/m2. Such excellent low weight, low thickness, and broadband electromagnetic wave absorption membrane may pave the way for new applications of OMIC-derived materials.