Graphene oxide-ferrite hybrid framework as enhanced broadband absorption in gigahertz frequencies

Abstract

The present investigation is focused on the in-situ synthesis of Graphene oxide (GO)-ferrite nanoparticle hybrid framework by gel-combustion method followed by fabrication of homogeneous, structurally stable thin (~100–120 μm) hybrid-polyurethane coating on a metallic aluminum substrate and its application on the properties of broadband absorption over the microwave frequency region. Microstructure studies of hybrid materials illustrated that small sized ferrite nanoparticles (~17 nm) are grafted on and through the graphene layers, which forms a homogeneous coating thereby. The hybrid-nanocomposite coating demonstrated superior broadband absorption properties with absorptivity higher than 90% throughout a bandwidth of ~6 GHz, and moreover, it was found that with increased loading of GO in the nanocomposite, the bandwidth range of absorption frequency increases with enhanced absorptivity. The real part and imaginary part of the surface impedance values of the coating was obtained as 377 Ω and 0 Ω, respectively, which imply that the free-space impedance of the hybrid-nanocomposite coating is matching correctly. The nanocomposite coating showed ultra-high absorptivity over the frequency band of 8–12 GHz, which has numerous practical applications as radar absorbing materials (RAM), stealth technology, electromagnetic shielding, and radiated electromagnetic interference (EMI) management in onboard spacecraft and many more.

Structural, magnetic, and gigahertz-range electromagnetic wave absorption properties of bulk Ni–Zn ferrite

“…Dielectric 14 , magnetic 15 , and carbon-based 16 , 17 materials could be utilized as EM wave absorbers in order to attenuate the distinct frequency range and reducing the interference caused by airborne connections 18 . In addition to the attenuation ability, which is related to dielectric and magnetic losses, another challenging issue is that an absorber material should fulfill the impedance matching condition to receive incident EM waves with the lowest reflectivity.…”

Fabrication of chitosan-coated mixed spinel ferrite integrated with graphene oxide (GO) for magnetic extraction of viral RNA for potential detection of SARS-CoV-2

“…The diffraction patterns for CHLZFO and CHLZFO-GO NCs found analogous to the diffraction patterns of LZFO, thereby revealing that no significant variation was observed in the orientation of NPs in the respective nanocomposites. The absence of diffraction peaks of CH and GO in respective XRD patterns of CHLZFO and CHLZFO-GO illustrated the successful coating of chitosan on LZFO NPs and the successful exfoliation of GO to a large extent with successful deposition of CHLZFO NPs on it, indicating the formation of nanocomposite [ 57 ]. The noise observed in the XRD patterns of CHLZFO and CHLZFO-GO NCs, respectively, is attributed to the amorphous nature of chitosan.…”

Graphene-based wide band semi-flexible array antenna with parasitic patch for smart wireless devices

“…There are many deposition techniques to grow graphene on a specific substrate. Graphene deposition synthesis on SiO 2 or in-situ Ni 0.5 Zn 0.5 Fe 2 O 4 ferrite nanoparticle with grafted-graphene oxide hybrid scaffold for broadband microwave absorber material is clarified in [5,6]. One can achieve mass productivity and uniformity of the material with that chemical vapour deposition (CVD) process.…”