Synthesis of hollow poly(aniline-co-pyrrole)–Fe3O4 composite nanospheres and their microwave absorption behavior

Abstract

Hollow poly(aniline-co-pyrrole)-Fe 3 O 4 (HPAP-Fe 3 O 4 ) nanospheres with significant electromagnetic properties were successfully prepared via the oxidative polymerization of a mixture of aniline and pyrrole in the presence of a magnetic fluid, using a non-ionic surfactant as a template.The products were characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetric analysis and X-ray photoelectron spectroscopy. The electromagnetic (EM) and microwave absorbing properties of the nanocomposites were also investigated. The HPAP-Fe 3 O 4 nanospheres exhibit superparamagnetic properties, and the conductivity increases with Fe 3 O 4 content. The reflection loss evaluation based on the absorbing wall theory at 2 mm thickness shows that the reflection loss is reinforced in the frequency range of 0.5-10 GHz by the presence of Fe 3 O 4 nanoparticles, and the frequency of minimum reflection loss shifts to a higher value with increasing Fe 3 O 4 content. HPAP-Fe 06 exhibits the best microwave absorbing property between 0.5 and 10GHz.

Microwave absorption behaviour of MWCNT based nanocomposites in X-band region

“…This plots showed some negative values at different portion which might be due to the noise [44]. Addition of Fe 3 O 4 particle may cause the hysteresis loss and eddy current loss which is responsible for magnetic loss [45]. Hence, the permittivity and permeability data supported the microwave absorption results of the prepared RAMs.…”

Enhanced microwave absorption properties of N-doped graphene@PANI nanorod arrays hierarchical structures modified by Fe3O4 nanoclusters

“…The reason is that the embedment of Fe 3 O 4 nanoclusters with low conductivity could reduce the effective doping of proton acid and destroy the conjugated structure of the PANI nanorod arrays, which results the decrease of conductivity and therefore the permittivity decreases [27]. In addition, e 00 exhibits a strong resonance peak at 14.3 GHz, which is maybe caused by the nature of the interface between the Fe 3 O 4 nanocluster and the PANI, and polarization by the Fe 3 O 4 nanocluster [28]. As for the complex permeability, the values for m 0 are all approaching to 1 and have no conspicuous difference with NG@PANI nanorod arrays (m 0 = 1),…”

Fabrication of rechargeable lithium ion batteries using water-based inkjet printed cathodes

“…Samples with low initial pH values show lower terahertz transmission intensity than the same with an initial pH value close to 9.13. It has been confirmed that the presence of conductive impurities such as: FeO or Fe 3 O 4 could not decrease the conductivity of dried powder [28,29]. However, FeO or Fe 3 O 4 impurities in samples A, B, C can be oxidized into Fe 2 O 3 eventually; the presence of Fe 2 O 3 impurity not only lowers the electrical conductivity of the electrodes, but also causes consumption of LiFePO 4 , as discussed above.…”