Graphene-ferrites interaction for enhanced EMI shielding effectiveness of hybrid polymer composites

Hybrid polymer composites based on poly vinylidene fluoride (PVDF) matrix are fabricated by dispersion of few layered graphene (FLG) and nickel spinal ferrites (NSF) for improving EMI shielding effectiveness. The FLG loading is kept constant at 3 wt% while NSF content is varied from 15-30 wt% in PVDF using solution processing technique. The shielding effectiveness in the frequency domain of 1-12 GHz is enhanced ranging 25 dB-45 dB for PVDF/FLG composite as compared to similar to 0 dB for neat PVDF. With addition of NSF up to 15 wt%, the attenuation is increased to 30 dB-53 dB, clearly indicating the effective interaction and network formation of FLG and NSF in PVDF matrix. Moreover, the shielding effectiveness trend is reduced to 12 dB-43 dB as the NSF loading is increased to 30 wt% owing to its agglomeration. Absorption is the dominant phenomena in obtaining the total shielding effectiveness of similar to 53 dB for PVDF/FLG-3 wt%NSF-15 wt% hybrid polymer composites. Additionally, the I-V curves provide the electrical conductivity trend while scanning electron microscope (SEM) confirms the network formation in hybrid composite.