Superior electromagnetic wave absorption performance of Fe3O4 modified graphene assembled porous carbon (mGAPC) based hybrid foam

High performance Fe3O4 modified graphene assembled porous carbon (mGAPC) based epoxy paint coated on Polyethylene (PE) foam is realized by spray technique to fabricate light weight electromagnetic absorbers. The mGAPC as a pigment in a standard composition of commercial paint was optimized and the influence of solvent and additives are studied to achieve X-band (8.2-12.4 GHz) electromagnetic wave absorption (EA) in the hybrid foam (HF). From the comparative studies, the hybrid foams obtained from epoxy paint with toluene as solvent (without Mn-octate as additive) showed a Reflection Loss (RL) -19 dB (in the range of 8.3-8.7 GHz), which was further increased with the coating cycles up to -43 dB (in 10.2-11.2 GHz).The observed rise is attributed to increase in localized interfacial polarization that arises at the combined interfaces of mGAPC. The result showed 99% loss, which projects a promising EA paint for practical applications. Further thickness dependent studies of EA in Paint Coat HF1, reveals that with increasing thickness from 0.3 to 2 mm, the RL also increases from -19 to -43 dB with changing absorption band. The superior EA properties are correlated to the percolation threshold, pigment dispersibility and further correlated to the strong absorption, destructive interference, multiple internal reflections and interfacial polarization of the radiation in the hybrid foam. Moreover, considering the paint lowest thickness similar to 0.3 mm with -19 dB of RL, the hybrid foam promises a cost-effective, fine, light-weight EA/ RL material for secure electronic devices and packaging in civil and defence applications.

Automated summary

By optimizing the use of mGAPC pigment in epoxy paint, lightweight electromagnetic absorbers based on PE foam were successfully fabricated. The absorption of electromagnetic waves in the hybrid foam was significantly improved after multiple coating cycles.