Facile design of a ZnO nanorod–Ni core–shell composite with dual peaks to tune its microwave absorption properties

Abstract

The Ni/ZnO composites show two wide attractive absorption bands, which could broaden the effective absorption bandwidth.

Controlling the electric permittivity of honeycomb-like core–shell Ni/CuSiO3 composite nanospheres to enhance microwave absorption properties

“…The greatest RLs were À23.5 dB at 11. wider effective bandwidth) of the present composite nanospheres with that of other reported Ni-based composites. 9,17,20,[34][35][36][37][38][39] The superior performance of the prepared absorbers suggests that the honeycomb-like core-shell structure contributed signicantly to the microwave absorption. Dielectric loss, magnetic loss, shell thickness, and geometry affected performance.…”

“…3 r and m r are the relative complex permittivity and permeability, respectively, and are expressed as 3 r ¼ 3 0 À j3 00 and m r ¼ m 0 À jm 00 . 2,9,17,20 3…”

“…4,11,12 Various types of core-shell composite microstructures have been reported based on Ni as the core material and different shell materials including polymers, C, SnO 2 , TiO 2 , SiO 2 , ZnO, ZnS, CuO, and graphene composites. 9,[13][14][15][16][17][18][19][20] Zhao et al reported ZnS-wrapped Ni spheres that exhibited a reection loss (RL) of À42.4 dB with high effective bandwidth. 17 Deng et al prepared ZnO nanorod-coated Ni spheres and reported an RL of À30.2 dB.…”

“…17 Deng et al prepared ZnO nanorod-coated Ni spheres and reported an RL of À30.2 dB. 20 Zhao et al reported Ni@TiO 2 and Ni@SiO 2 core-shell composites and found that the SiO 2 shell had better microwave absorption properties and anti-oxidation capability than pure Ni or Ni@TiO 2 . 9 These reports concluded that the coating material plays a decisive role in obtaining good EM wave absorption properties through impedance matching, cooperation between the EM parameters (3, m), core and shell synergistic effects, and interfacial polarizations.…”

Recent progress on nanostructured conducting polymers and composites: synthesis, application and future aspects

“…Therefore, shielding of EMI is very critical for telecommunication signals, electronic device performance, industries operation and human life. Effective EMI shielding must have two functions of reducing undesirable emissions and protecting the component from stray external signals [407][408][409]. EMI shielding effectiveness (SE) is an important parameter to evaluate the absolute effectiveness of shielding materials and is strongly dependent on electrical conductivity and thickness of the shielding materials [410].…”