Nanostructured graphene/Fe3O4 incorporated polyaniline as a high performance shield against electromagnetic pollution

Abstract

The development of high-performance shielding materials against electromagnetic pollution requires mobile charge carriers and magnetic dipoles. Herein, we meet the challenge by building a three-dimensional (3D) nanostructure consisting of chemically modified graphene/Fe3O4(GF) incorporated polyaniline. Intercalated GF was synthesized by the in situ generation of Fe3O4 nanoparticles in a graphene oxide suspension followed by hydrazine reduction, and further in situ polymerization with aniline to form a polyaniline composite. Spectroscopic analysis demonstrates that the presence of GF hybrid structures facilitates strong polarization due to the formation of a solid-state charge-transfer complex between graphene and polyaniline. This provides proper impedance matching and higher dipole interaction, which leads to the high microwave absorption properties. The higher dielectric loss (ε'' = 30) and magnetic loss (μ'' = 0.2) contribute to the microwave absorption value of 26 dB (>99.7% attenuation), which was found to depend on the concentration of GF in the polyaniline matrix. Moreover, the interactions between Fe3O4, graphene and polyaniline are responsible for superior material characteristics, such as excellent environmental (chemical and thermal) degradation stability and good electric conductivity (as high as 260 S m(-1)).

Multi-walled carbon nanotube–graphene–polyaniline multiphase nanocomposite with superior electromagnetic shielding effectiveness

“…During the past decade, improvements in EMI shielding effectiveness (SE) have been achieved by introducing carbon materials, such as carbon black, carbon ber, exfoliated graphite, graphite, yash, carbon nanotubes (CNTs) and even now multilayer graphene. 12,[15][16][17][18][19] To improve the properties of the PANI, Saini et al 15 developed PANI based composite by in situ emulsion pathway technique with a different ratio of graphite and PANI. It is reported that by incorporating 15.6 wt% of graphite in PANI, the ultimate composite possesses electrical conductivity 12.5 S cm À1 and total EMI-SE is reached up to À33.6 dB in the X-band frequency region .…”

MnO2 decorated graphene nanoribbons with superior permittivity and excellent microwave shielding properties

“…When the total EMI shielding effectiveness of the material is more than À10 dB, then loss due to multiple reections (SE M ) becomes negligible and can be neglected. 34,38,39 Thus, the total shielding effectiveness (SE T ) can be expressed as…”

Emi Shielding Effectiveness of Composites Based on Barium Ferrite, Pani, and MWCNT

“…To overcome the aforementioned problems, researchers have since developed hybrid materials that combine several shielding materials to offset respective limitation of the materials while still retaining its enhanced shielding properties. Various combinations of materials with optimum shielding capabilities have since been developed [7,9,[16][17][18].…”

“…For example, hexagonal ferrites have long been known to possess salient properties such as good chemical stability [2], large crystal anisotropy [3,4], and big values of permeability [5,6], enabling it to exhibit good electromagnetic wave absorbing properties. The discovery of its high electrical conductivity have renewed interests in the intrinsically conducting polymer (ICP), polyaniline (PANI), and its possible applications for microwave absorption [7][8][9]. Carbon based shielding materials have seen widespread adoption in various fields of application due to their light weight and are known to show good electrical properties [10].…”