New insight into the shape-controlled synthesis and microwave shielding properties of iron oxide covered with reduced graphene oxide

Abstract

We proposed various approaches for the shape-controlled synthesis of iron oxide-RGO composites to evaluate the effect of different morphologies on their microwave shielding properties. The nature of various ferrite structures (flakes, cubes and rods) covered by reduced graphene oxide multilayers has been investigated using X-ray diffraction, Raman spectroscopy, FT-IR, scanning electron microscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopic techniques.The electromagnetic interference (EMI) shielding effectiveness of iron oxide of different shapes coated with reduced graphene oxide was investigated in the Ku band frequency range (12.4-18 GHz). The rod shaped iron oxide covered with reduced graphene oxide sheets demonstrates the highest shielding effectiveness value of $33.30 dB (>99.9% attenuation) as compared to flake and cube shaped iron oxides due to the combined effect of magnetic losses (hysteresis, eddy current loss and effective anisotropy) and dielectric losses (space charge polarization, interfacial polarization, surface defects, multiple scattering, etc.). These innovative proposed structures and their obtained EMI shielding results deliver a new insight into the morphology dependent nature of iron oxides covered with RGO nanosheets and create new opportunities for next generation EMI materials.

Polypropylene Nanocomposite Filled with Spinel Ferrite NiFe2O4 Nanoparticles and In-Situ Thermally-Reduced Graphene Oxide for Electromagnetic Interference Shielding Application

“…Further, a number of studies on EMI shielding properties of spinel ferrite with graphene have been reported by researchers [13,14,15]. However, there are few studies on EMI shielding properties of nanocomposites consisting of NiFe 2 O 4 spinel ferrite nanoparticles with graphene.…”

Mechanism and kinetics of magnetite oxidation under hydrothermal conditions

“…[1][2][3][4][5][6][7][8][9][10] Hybrids composed of iron oxides and graphene also have numerous promising uses. [11][12][13][14] The iron oxides that can be employed in this manner include magnetite (Fe 3 O 4 ), maghemite (g-Fe 2 O 3 ) and hematite (a-Fe 2 O 3 ) ( Fig. 1).…”

Enhanced electromagnetic shielding behaviour of multilayer graphene anchored luminescent TiO2 in PPY matrix

“…Further, the imminent increase in the microwave absorption properties of the PPY/0.05 M/ 0.05/T can be related to the both complex and real part of permittivity of nano size of TiO 2 particles. Due to the small size, the anisotropic energy of the particles will be high and the increased anisotropy energy contributes to the enhancement of microwave absorption [15]. Besides the small size of TiO 2 particles, the efficient decoration of TiO 2 particles on MLG sheets lead to the increased polarization charges on the surface.…”