FeCo/Graphene Nanocomposites for Applications as Electromagnetic Wave-Absorbing Materials

Abstract

Simple and efficient preparation high-performance magnetic carbon-based nanocomposites as electromagnetic wave-absorbing materials is a research hotspot. Here, employing a straightforward, ecologically friendly, and effective solid-state technique, FeCo/graphene nanocomposites with good electromagnetic wave absorption capabilities were successfully fabricated without the use of any external carbon sources. m-NaCl powder is combined with Co(acac)2 and Fe(acac)3 and then annealed at a particular temperature. During the annealing process, FeCo nanoparticles were synthesized and supported on graphene nanocomposites. Following annealing at 700 °C, the material showed an ideal reflection loss of −71.63 dB at 10.8 GHz, an effective bandwidth of 4.24 GHz, and a thickness of 2.68 mm. The radar cross section (RCS) of FeCo/C-700 is less than −10 dB m2, which provides evidence that the samples have good radar wave attenuation capabilities when the scattering angle is between 0 and 60°. The approach for creating graphene composites with FeCo nanoparticles suggested in this study serves as a crucial source of inspiration for the later development of new magnetic carbon nanocomposite systems.

Influence of Exfoliated Boron Nitride for Fabrication of a Lightweight Wideband Microwave Absorbing Material

“…If the magnetic loss results from the Eddy current loss, the values of C 0 ( C 0 μ″(μ′) −2 f –1 ) are unaffected by frequency fluctuations. , It is possible that the Eddy current loss is not the primary magnetic loss mechanism for the sample of 15-NiFBN-0.75 because of a significant fluctuation in 9.9 GHz (Figure b). However, the magnetic loss mechanism for 15-NiFBN-0.5 and 15-NiFBN-1 samples may be attributed to the Eddy current loss dominated since the C 0 values are almost unchanged throughout the range of 8.2–12.4 GHz.…”

“…The AC had a tight relationship with dielectric and magnetic loss abilities. The AC (α) might be estimated using the results of earlier studies (eq ): , 0.25em α = 2 π f c ( μ ″ ε ″ − μ ′ ε ′ ) + false( μ ″ ε ″ prefix− μ ′ ε ′ false) 2 + false( μ ′ ε ″ prefix− μ ″ ε ′ false) 2 …”

“…RL measures how well microwave-absorbing materials effectively absorb microwaves. The following is a description of RL curves in terms of transmission line theory (eq ): , RL ( dB ) = 20 log | ( z in − z 0 ) ( z in + z 0 ) | …”

“…The AC had a tight relationship with dielectric and magnetic loss abilities. The AC (α) might be estimated using the results of earlier studies (eq 6): 67,68 RL measures how well microwave-absorbing materials effectively absorb microwaves. The following is a description of RL curves in terms of transmission line theory (eq 7): 67,69 (7) The following equation may be used to represent Z in , which is the absorbing material's input impedance in this case (eq 8): (8) where f is the frequency, c is the speed of an EM wave in free space, d is the thickness of the absorber, and ε r and μ r are the relative permittivity and permeability, respectively.…”

Acrylonitrile Butadiene Styrene-Based Composites with Permalloy with Tailored Magnetic Response

“…At least two different materials are involved in the development of polymer-based magnetic composites: the magnetic particles (inorganic component) and the polymeric matrix (organic component). Magnetic nanomaterials typically include iron oxides [ 9 , 10 ], cobalt iron oxides [ 11 ], magnetic alloys of nickel, cobalt and/or iron [ 12 ] and rare-earth containing particles [ 13 ], although strong efforts are being devoted to rare-earth free materials. The different types of magnetic materials, their geometry and dimensions, among other conditions, confer the composite distinct magnetic properties, such as superparamagnetism, ferromagnetism (with varying degrees of magnetic hardness) and antiferromagnetism.…”