Interface Polarization Strategy to Solve Electromagnetic Wave Interference Issue

Abstract

Design of an interface to arouse interface polarization is an efficient route to attenuate high-frequency electromagnetic waves. The attenuation intensity is highly related to the contact area. To achieve stronger interface polarization, growing metal oxide granular film on graphene with a larger surface area seems to be an efficient strategy due to the high charge carrier concentration of graphene. This study is devoted to fabricating the filmlike composite by a facile thermal decomposition method and investigating the relationship among contact area, polarization intensity, and the type of metal oxide. Because of the high-frequency polarization effect, the composites presented excellent electromagnetic wave attenuation ability. It is shown that the optimal effective frequency bandwidth of graphene/metal oxide was close to 7.0 GHz at a thin coating layer of 2.0 mm. The corresponding reflection loss value was nearly -22.1 dB. Considering the attenuation mechanism, interface polarization may play a key role in the microwave-absorbing ability.

Broadening Electromagnetic Absorption Bandwidth: Design from Microscopic Dielectric‐Magnetic Coupled Absorbers to Macroscopic Patterns

“…Furthermore, alternative methods including using frequency selective radar absorbing materials, graded-dielectric multilayer, and employment of concise design of the microscopic structures of the fillers are promising methods for achieving high-performance microwave absorption materials and composites. [41][42][43][44][45][46][47] Moreover, the mechanical properties and the significant factors that impact the performance should be concerned. [48][49][50][51][52][53] Figure 12 displays the effective absorption bandwidth of the materials and structures.…”

Electromagnetic wave absorbing properties of glucose‐derived carbon‐rich SiOC ceramics annealed at different temperatures

“…Figure 6 shows the real (ε′) and imaginary (ε″) part of the relative complex permittivity, the dielectric tangent loss (tanδ = ε″/ε′) and the ε′-ε″ curves of the nanocomposites in 2-18GHz. 29,[32][33][34][35] where ε s is the static permittivity at infinite frequency, ε ∞ is the relative dielectric permittivity at infinite frequency. It is well established that the ε′ represents the storage capability of electric energy, while the ε″ is related to the microwave attenuation capability of the material.…”

Development of a hollow carbon sphere absorber displaying the multiple-reflection effect to attenuate electromagnetic waves

“…Generally, a Raman spectrum of a carbon material shows two peaks, at 1350 and 1590 cm À1 , corresponding to the D and G bands, respectively. [29][30][31] Commonly, the ratio of the intensity of the D band (I D ) to that of the G band (I G ) represents the graphitization level. A low I D /I G ratio value is indicative of good levels of graphitization and conductivity.…”