Synthesis and microwave absorption property of flexible magnetic film based on graphene oxide/carbon nanotubes and Fe₃O₄nanoparticles

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

“…3, we can see that the curves have a slight weight loss below 250 C, which can be ascribed to the evaporation of H 2 O or removal of surface functional groups. 44 The main weight loss between 250 C and 600 C is related to the oxidation of rGO and carbon and the transformation from FeNi alloy to metal oxide. As the rGO and carbon components are completely combusted in air, the residual products are a mixture of Fe 2 O 3 and NiO, so the total content of rGO and carbon can be calculated by…”

Facile solvothermal synthesis of novel hetero-structured CoNi–CuO composites with excellent microwave absorption performance

“…Commonly, the resonance frequency depends on the anisotropy eld, which is closely related to the coercivity value of the materials. 46 Anisotropy would increase to optimal state with increasing CuO content, which would be greatly helpful to improve electromagnetic waves absorption properties. From 5-18 GHz, the values of C 0 ¼ m 00 (m 0 ) À2 f À1 are nearly constant and this is called the skin-effect criterion, 47 suggesting that the eddy current loss mainly affected the dissipation of microwave energy.…”

Strengthened electromagnetic absorption performance derived from synergistic effect of carbon nanotube hybrid with Co@C beads

“…The transformation of magnetic energy to electric energy indicates that, at high frequency, the EM absorption is mainly ascribed to the dielectric loss in the CNTs/Co@C hybrid. The negative permeability value and totally contrary variation trend of tangent loss have also been observed in other magnetic carbon hybrids such as CNTs/wax composite [49], Fe/Co/Ni nanoparticle-coated carbon nanofibers [50], graphene oxide/ CNT-Fe 3 O 4 composite [10], and porous carbon/Co hybrid [51]. To reveal the EM wave absorption performances of the CNTs/Co@C hybrid, the RL values were calculated according to Eqs.…”

“…Its large surface area and unique tubular morphology facilitate high loading of magnetic components, and meanwhile the superior electrical property promotes attenuation of incident EM wave. In the past years, some ferrites such as Fe 3 O 4 , CoFe 2 O 4 , have been frequently employed to serve as magnetic components in the magnetic CNTs hybrids [10,30,31]. In contrast with these traditional ferrites, magnetic metals (e.g., Fe, Co, Ni, and their alloys) own larger saturation magnetizations and higher Snoek's limits, which make them as better magnetic components for CNTs-based EM absorbers.…”

“…Nowadays, electromagnetic interface (EMI) deriving from the rapid development of wireless devices and radar systems have drawn great interest in exploiting highly effective EM absorption materials to address serious EMI issues [1][2][3][4][5][6][7][8][9][10][11][12]. Generally, an ideal EM absorber should satisfy the requirements of light weight, strong absorption, wide absorption frequency range, and thin matching thickness.…”