Excellent microwave absorption performance of LaFeO3/Fe3O4/C perovskite composites with optimized structure and impedance matching

Synthesis of nitrogen-doped graphene aerogels modified by magnetic Fe3O4/Fe/C frameworks as excellent dual-band electromagnetic absorbers

“…C 0 remains constant with the increase of frequency, indicating that eddy current loss is the main cause of magnetic loss. 46,47 As displayed in Fig. 6(h), the C 0 of S2 and S3 shows an overall downward trend with increasing frequency, manifesting that eddy current loss should not be responsible for magnetic loss.…”

“…Generally, the magnetic loss mainly originates from exchange resonance, eddy current loss and natural resonance in the gigahertz range. 46,47 The eddy current loss is related to the diameter of nanoparticles ( d ) and electrical conductivity ( σ ), which can be expressed by the following equations: 46,47 μ ′′ ≈ 2π μ 0 ( μ ′) 2 σd 2 f /3 C 0 = μ ′′( μ ′) −2 f −1 where μ 0 represents the vacuum permeability, f denotes the frequency, and C 0 signifies the eddy current coefficient. C 0 remains constant with the increase of frequency, indicating that eddy current loss is the main cause of magnetic loss.…”

“…6(h), the C 0 of S2 and S3 shows an overall downward trend with increasing frequency, manifesting that eddy current loss should not be responsible for magnetic loss. 46,47 Usually, natural resonance causes magnetic loss at low frequencies. 46,47 Therefore, the obvious increase of C 0 at low frequencies indicates the existence of natural resonance for S2 and S3.…”

“…46,47 Usually, natural resonance causes magnetic loss at low frequencies. 46,47 Therefore, the obvious increase of C 0 at low frequencies indicates the existence of natural resonance for S2 and S3.…”

A Novel Low-Density-Biomass-Carbon Composite Coated with Carpet-like and Dandelion-Shaped Rare-Earth-Doped Cobalt Ferrite for Enhanced Microwave Absorption

“…Meanwhile, the imaginary components ε ″ and μ ″ denote the dissipation capacity of the EW energy, within the material [ 54 , 55 ]. Secondly, when the EW is incident to the material surface, results from the disparity in impedance between the absorber and the surrounding medium, a segment of the EW is reflected to free space but cannot enter the absorbing body [ 56 , 57 ]. The impedance behaviors of the material are dependent on its ε r and μ r .…”