Exploring the Ni 3d Orbital Unpaired Electrons Induced Polarization Loss Based on Ni Single‐Atoms Model Absorber (Adv. Funct. Mater. 7/2023)

NiCo2O4/Hollow Mesoporous Carbon Nanosphere Hybrids Enabling Super‐Hydrophobicity, Thermal Insulation, and Highly Efficient Microwave Absorption

“…[ 46 ] In addition, the electron transfer between Ni 2+ and Co 3+ in NiCo 2 O 4 (like “superexchange”) can decrease the resistivity and increase the eddy current loss. [ 47 ] However, previous research has revealed that the natural resonance of magnetic domains plays a major role in the magnetic loss of ferrite materials in the radar band. [ 48 ] It is demonstrated that the energy of the alternating electromagnetic field can be adequately attenuated when its angular frequency matches the resonance frequency of ferrites.…”

Constructing Multiphase‐Induced Interfacial Polarization to Surpass Defect‐Induced Polarization in Multielement Sulfide Absorbers

“…From the complex permittivity curves, it is hard to summarize the variation pattern only based on the values, because the complex permittivity is controlled by the synergistic contributions of the phase‐separation components. In order to assess the merits of EM parameters, we predicted the range of complex permittivity that satisfy the ideal absorption properties (RL < −10 dB) at specified frequency points, [ 43 ] Figure S15 (Supporting Information). All of the predictions are based on a given permeability ( μ ′ = 1 and μ ″ = 0) and thickness ( d = 2.00 mm), and the results have been marked with arrows.…”

Confined In‐Situ Encapsulation of Co/C Composites with Increased Heterogeneous Interface Polarization for Enhanced Electromagnetic Performance

“…Based on the formula, polarization‐induced dielectric loss can effectively enhance the dielectric loss performance of low conductivity MAMs, which is demonstrated by the tanδ ɛ (ɛ″/ɛ′) curves reflecting the dielectric loss capacity (Figure S6c, Supporting Information). To confirm the existence of polarization relaxation phenomenon, Cole‐Cole semicircle curves as shown in Figure S7 (Supporting Information) are also drawn according to Debye theory: [ 41 ] $$$$\begin{equation}{\left( {{\mathrm{\varepsilon ^{\prime}}} - \frac{{{{\mathrm{\varepsilon }}}_s + {{\mathrm{\varepsilon }}}_\infty }}{2}} \right)}^2 + \ {\left( {{\mathrm{\varepsilon ^{\prime\prime}}}} \right)}^2 = {\left( {\frac{{{{\mathrm{\varepsilon }}}_{\mathrm{s}} - {{\mathrm{\varepsilon }}}_\infty }}{2}} \right)}^2\ \end{equation}$$$$…”