Nanostructured ZrO₂/MWCNT Hybrid Materials: Fabrication, Characterization and Applications in Shielding of Electromagnetic Pollution

Abstract

<jats:p>ZrO<jats:sub>2</jats:sub>/MWCNT nanocomposites have been prepared by simple refluxing method and characterized by X-ray diffraction (XRD). Fourier-transform infrared spectroscopy (FTIR), and Raman analysis suggests chemical interactions present between zirconia and Multiwalled carbon nanotube (MWCNT) in the as prepared nanocomposites. Electromagnetic inteference shielding efficiencies (EMI SE) for the nanocomposites were found to increase with increasing amount of MWCNT loading. Highest EMI SE value of 29.1–30.5 dB was obtained for nanocomposite containing 15 wt% loading of MWCNT in the microwave frequency range of 2–8 GHz. This optimum performance is due to several factors like highest percentage of intermolecular H-bonding, highly defective, interconnected network structure, high conductivity and dielectric permittivities of the nanocomposites.</jats:p>

MWCNTs‐ZrO2 as a reusable heterogeneous catalyst for the synthesis of N‐heterocyclic scaffolds under green reaction medium

“…Weak peaks centered at 1,120 and 1,017 cm −1 appeared in the spectrum for the MWCNTs-ZrO 2 composite due to the stretching mode of the aromatic C=C and C-O groups, respectively, presenting different chemical environment. [48] These findings clearly signify successful incorporation of ZrO 2 into MWCNTs. XRD patterns of oxidized MWCNTs, ZrO 2 , and MWCNTs-ZrO 2 composites are shown in Figure 2.…”

“…[ 47 ] Therefore multi‐walled CNTs‐ZrO 2 (MWCNTs‐ZrO 2 ) composites have been used in the field of Electromagnetic interference shielding. [ 48 ] Hybridization of MWCNTs‐ZrO 2 composites has not been used in organic synthesis as a heterogeneous catalyst till now.…”

Room-Temperature One-Step Synthesis of Silver/Reduced Graphene Oxide Nanocomposites as an Excellent Microwave Absorber

“…The formation of an interconnected network structure at a critical percolation threshold can be described by the percolation theory. , …”

“…67 The formation of an interconnected network structure at a critical percolation threshold can be described by the percolation theory. 68,69 According to this where σ dc , σ f , f c , and t refer to the DC conductivity of a composite, the DC conductivity of conducting materials with a filler, the weight fraction of the conducting material at the percolation threshold, and the critical exponent, respectively. The log σ dc versus log (f − f c ) plot in the inset of Figure S4b shows a linear variation.…”

Tuning of Shells in Trilaminar Core@Shell Nanocomposites in Controlling Electromagnetic Interference through Switching of the Shielding Mechanism

“…Accordingly, variation of SE T versus frequency of PFS nanocomposites over the frequency range similar to SE R and SE A follows the order The enhanced EMI SE in Fe 3 O 4 @SiO 2 @PPy could be explained by considering the role of dual interfaces (Fe 3 O 4 @ SiO 2 and SiO 2 @PPy) in EM attenuation because of interfacial polarization, 71 void space existing between Fe 3 O 4 and SiO 2 providing more active sites for reflection/scattering of EM waves, as observed in BET analysis mentioned earlier. 72 The superior SE T value in all Fe 3 O 4 @SiO 2 @PPy nanocomposites could be explained on the basis of reflection as the major contribution when compared to reflection. Our findings also show the highest shielding efficiency (SE T ≈ 32 dB) of synthesized PFS-10 over the frequency range of 2−8.5 GHz following reflection as the dominant shielding mechanism.…”