Egg white-derived carbon/magnetic nanoparticles/water-soluble graphene oxide composite with homogeneous structure as an excellent electromagnetic wave absorber

Abstract

An egg white-derived carbon/magnetic nanoparticles/water-soluble graphene oxide composite absorber (EWC/MNPs/WSGO) was specially designed and synthesized via a facile sol–gel process with subsequent high-temperature pyrolysis. Magnetic nanoparticles (MNPs) were used to bring magnetic loss ability and improve the electromagnetic matching condition. Water-soluble graphene oxide (WSGO) was also used to adjust the absorption properties of the composite absorber. Moreover, egg white, which is liquid biomass, enables uniform dispersion of MNPs and WSGO within the absorber, allowing full use of the synergistic effect of each component. Benefiting from the excellent homogeneous structure, moderate dielectric loss and magnetic loss, strongly matched impedance, and multiple polarization are achieved. The as-synthesized optimal sample (EWC/MNPs/WSGO-1.0) exhibits superior electromagnetic wave absorption properties. The minimum reflection loss (RL_min) reaches −51.5 dB, and the effective absorption bandwidth (EAB, RL < −10 dB) is 3.4 GHz at a thickness of 1.6 mm. Compared with the reported bio-derived carbonaceous composite absorbers, EWC/MNPs/WSGO has great potential to be a lightweight and efficient electromagnetic wave absorption material in the frequency range of 2 to 18 GHz.