Reduced Graphene Oxide/Fe₃O₄/Polyaniline Ternary Composites as a Superior Microwave Absorber in the Shielding of Electromagnetic Pollution

Abstract

The present work is focused on fabrication of reduced graphene oxide/iron(II/III) oxide/polyaniline (RGO/Fe 3 O 4 /PANI) ternary composite by a hydrothermal method, its characterization, and application in the development of a high microwave absorbing shielding material. The RGO/Fe 3 O 4 /PANI composite showed dramatic enhancement of dielectric loss and magnetic loss compared to Fe 3 O 4 /PANI and RGO/Fe 3 O 4 binary composites. This is ascribed to the embedment of more heterostructure phases. As a result, RGO/Fe 3 O 4 /PANI showed remarkably high SE T (∼28 dB) through the absorption dominant mechanism. Our findings also showed maximum R L of Fe 3 O 4 /PANI, RGO/Fe 3 O 4 , and RGO/Fe 3 O 4 /PANI in the range of 2–8 GHz corresponding to −25 to −35, −40 to −46, and approximately −64 dB, respectively. This is in all probability due to the good impedance matching between permittivity/permeability and dielectric/magnetic losses.

Fibers of Thermoplastic Copolyamides with Carbon Nanotubes for Electromagnetic Shielding Applications

“…The commonly used fillers are metals and metal oxides in the form of powders or particles (e.g., Ni, Cu, Fe, Co, ZnO, SiO 2 , TiO 2 , BaTiO 3 , etc. ), which are mixed with the polymers or are applied in the form of coatings [7,10,11]. The other possibility is to use fillers for the polymers in the form of short fibers such as carbon fibers, metal-coated carbon fibers, or stainless steel fibers [12,13].…”

Temperature‐Dependent Electromagnetic Microwave Absorbing Characteristics of Stretchable Polyurethane Composite Foams with Ultrawide Bandwidth

“…Both the μ′ and μ″ values of the composites were less than 1, possibly implying that φ ranged from π to 3/2 π , which occurred in some similar Fe 3 O 4 ‐based composites. [ 37,38 ]…”

Functionalized Graphene/Nickel/Polyaniline Ternary Nanocomposites: Fabrication and Application as Electromagnetic Wave Absorbers

“…The excellent microwave absorption properties of ternary composites can also be expressed in terms of reflection loss ( R L ). The R L can be mathematically expressed by applying a transmission line theory in the following equations: where Z in , f , and c represent the input impedance, frequency, and velocity of electromagnetic waves, respectively. In addition, d , ε r , and μ r represent the thickness, relative permittivity, and relative permeability of the examined sample, respectively.…”

“…The dipole polarization, electronic spin, and charge polarization of multi-interfaces and combination of dielectric/magnetic materials can facilitate achieving a reasonable degree of impedance matching. This can result in excellent microwave absorption properties in ternary composites, such as graphene/Fe 3 O 4 /PANI, − RGO/PANI/Co 3 O 4 , , Ni/PANI/RGO, FeCo/RGO/PPy, RGO/PANI/FeNi 3 , Graphene-PANI-Fe 3 O 4 , − RGO/PPy Nanotube/Fe 3 O 4 Aerogel, Fe 3 O 4 @C@PANI, Fe 3 O 4 @SiO 2 @PPy, PANI/Ni@graphene, and GO/PANI/Fe 3 O 4 . , In addition, FeNi 3 @SiO 2 /RGO-PANI, CuS/RGO/PANI/Fe 3 O 4 , Graphene@Fe 3 O 4 @WO 3 @PANI, and Graphene@Fe 3 O 4 @PANI@TiO 2 quaternary composites also reveal their excellent microwave absorption properties. According to an exclusive literature survey, there are very limited research studies conducted on graphene, Ni, and PANI composites as EMI shielding materials.…”