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

Abstract

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 ∼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 ∼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.

Study of dielectric and electromagnetic shielding behaviour of BaTiO3‐CoFe2O4 filled LDPE composite

“…When an electromagnetic wave is incident on the surface of the material some waves is transmitted and some are reflected back. Shielding effectiveness can be positive or negative it depends upon the method we follow 25,26 . The equation used for calculating the electromagnetic interference shielding effectiveness is given by where P in and P out are the power of incident and transmitted electromagnetic wave.…”

“…Shielding effectiveness can be positive or negative it depends upon the method we follow. 25,26 The equation used for calculating the electromagnetic interference shielding effectiveness is given by…”

Electromagnetic interference of nickel ferrite and copper ferrite filled low-density polyethylene composite

“…The Shielding effectiveness values are determined using reflection, absorption and transmission expressed as R, A, and T respectively. 17,18 …”

“…In literature, Ahmed et al. 17 deposited PVDF/NSF and found that with addition of NSF up to 15% the attenuation is increased to 30 dB – 50 dB, but as the NSF loading is increased to 30% the shielding effectiveness tended to reduce with increase in NSF loading owing to agglomeration. Targhagh et al.…”

Hybrid materials for electromagnetic shielding: A review

“…The presence of Fe 3 O 4 nanoparticles (Figure 26D) also enhanced absorption by improving the level of impedance matching. Ahmed et al [75] fabricated an absorption-dominated hybrid composite based on the few-layered graphene (FLG) nanosheets and nickel spinel ferrites (NSF) for EMI shielding application in a 1-12 GHz frequency regime. For PVDF/FLG-3 composite, the shielding value is between 25 and 32 dB at 2 GHz reaching up to 35-40 dB at 5-9 GHz.…”