Electrostatic Encapsulation of Cobalt Ions into Crystalline Framework Derived Polymer Aerogel: Ultra-light, Pressure Resistant, Hydrophobic, Photothermal Conversion, Heat Insulation and Infrared Stealth

A variety of electromagnetic wave absorption materials (EMWAs) have been reported, but the integration of powder materials and multifunctional devices should be investigated in-depth to adapt to practical demands. Herein, carbon-coated cobalt composites were prepared by adsorbing magnetic metal cations into an anionic crystalline framework through an electrostatic encapsulate process. Excellent reflection loss (RL_min) of −40.49 dB and effective absorption bandwidth (EAB) of 5.36 GHz (RL<−10 dB, 10.4–15.76 GHz) was achieved with an optimal radar cross section (RCS) reduction of 34.9 dB·m² for the sample tested. For commercial applications, Co@CN-4 was integrated into sodium carboxymethyl cellulose (CMC) aerogel to create an ultra-lightweight composite aerogel that is compressive resistant and heat-holding while also having photothermal conversion capabilities.The hydrophobic modification makes it more widely useful. This study provides a new strategy for EWAMs to integrate versatility and improve their application prospects.