Egg-white-derived magnetic carbon flakes with enhanced microwave absorption properties

Abstract Biomass derivatives are being extensively studied for microwave absorption because of their simple and environment-friendly preparation process. Herein, we report a facile and low-cost method wherein egg white is used as a carbon and sulfur source for the first time. Meanwhile a trimetallic alloy derived from cobalt nitrate, ferric nitrate, and nickel nitrate is used as the magnetic component to fabricate microwave absorption materials. The amount of alloy can regulate the microwave absorption performance of egg-white-derived carbon. The strongest reflection loss (−47.09 dB) of the obtained composites can be achieved at 13.8 GHz with an ultrathin thickness (1 mm). The analysis of dielectric and magnetic constant reveals that the introduced alloy affects dielectric loss while increasing the amount of alloy affect magnetic loss more obviously. This study not only evidences that egg-white-derived carbon flakes can absorb microwaves but also reveals the role of alloy introduction in enhancing microwave attenuation capability.