Economical synthesis of composites of FeNi alloy nanoparticles evenly dispersed in two-dimensional reduced graphene oxide as thin and effective electromagnetic wave absorbers

Abstract

a Developing electromagnetic wave absorbing materials prepared by a facile and economical way is a great challenge. Herein, we report a feasible route to synthesize a series of two-dimensional FeNi/rGO composites by a hydrothermal method followed by a carbonization process. The characterization confirms that nano-sized FeNi alloy nanoparticles are evenly supported onto graphene sheets without aggregation. The homogeneous dispersion of the nanoparticles may result from the introduction of glucose and the oxygen-containing groups on the surface of the graphene oxide. Measurements show that the microwave attenuation capability of the composites can be improved dramatically by adjusting the proportion of dielectric and magnetic components. Consequently, the two-dimensional magnetic material (FeNi/rGO-100) exhibits an excellent microwave absorption performance. In detail, the minimum reflection loss of À42.6 dB and effective bandwidth of 4.0 GHz can be reached with a thinner thickness of 1.5 mm. This study demonstrates that synergistic effects among the magnetic particles, reduced graphene oxide and amorphous carbon layers give rise to the highlighted microwave attenuation ability. Overall, the FeNi/rGO composite is a promising candidate to be used as a microwave absorber, and the feasible and economical method has shown potential application to construct multitudinous two-dimensional materials.

Reduced graphene oxide decorated with Ni-Fe-Mo permalloy obtained by sputtering

“…2b,c). There is in both cases a sharp decrease in weight resulting from the combustion of carbon atoms in rGO skeleton comprising carbon and oxygen functional groups [34][35][36]. However, in rGO the initial degradation temperature is of 376 • C ending at 650 • C and in permalloy/rGO initiates at 420 • C and ends at 690 • C showing a stabilization effect of the metals in rGO degradation.…”

Dopamine-derived cavities/Fe3O4 nanoparticles-encapsulated carbonaceous composites with self-generated three-dimensional network structure as an excellent microwave absorber

“…The area ratio of these two bands (I D /I G ) is a common indicator of the disorder degree, and its increasing value manifests the formation of defects. 31 The I D /I G values were calculated to be 0.15, 1.72, 1.70, 1.76 and 1.68 for samples HDC, FC-700, HFC-700, HFC-800 and HFC-900, respectively. The tested HDC, derived from CPDA that calcined at 700 C and then treated with pickling, was not encapsulated by the carbonaceous matrix and was separately characterized by Raman.…”

Humins with Efficient Electromagnetic Wave Absorption: A By‐Product of Furfural Conversion to Isopropyl Levulinate via a Tandem Catalytic Reaction in One‐Pot

“…And the samples were compressed into toroidal rings with an inner diameter of 3.04mm and an outer diameter of 7.00mm by homogeneously mixing paraffin wax (60 %) and products (40 %). The reflection loss (RL) values were calculated by transmission line theory [32] …”