title: Absorption-Dominated Electromagnetic Wave Suppressor Derived from Ferrite-Doped Cross-Linked Graphene Framework and Conducting Carbon.
abstract: To minimize electromagnetic (EM) pollution, two key parameters, namely, intrinsic wave impedance matching and intense absorption of incoming EM radiation, must satisfy the utmost requirements. To target these requirements, soft conducting composites consisting of binary blends of polycarbonate (PC) and poly(vinylidene fluoride) (PVDF) were designed with doped multiwalled carbon nanotubes (MWCNTs) and a three-dimensional cross-linked graphene oxide (GO) framework doped with ferrite nanoparticles. The doping of α-MnO2onto the MWCNTs ensured intrinsic wave impedance matching in addition to providing conducting pathways, and the ferrite-doped cross-linked GO facilitated the enhanced attenuation of the incoming EM radiation. This unique combination of magnetodielectric coupling led to a very high electromagnetic shielding efficiency (SE) of -37 dB at 18 GHz, dominated by absorption-driven shielding. The promising results from the composites further motivated us to rationally stack individual composites into a multilayer architecture following an absorption-multiple reflection-absorption pathway. This resulted in an impressive SE of -57 dB for a thin shield of 0.9-mm thickness. Such a high SE indicates >99.999% attenuation of the incoming EM radiation, which, together with the improvement in structural properties, validates the potential of these materials in terms of applications in cost-effective and tunable solutions.
authors.affiliation: Department of Chemistry, National Institute of Technology , Durgapur, WB India 713209.
authors.forename: Sourav
authors.initials: S
authors.lastname: Biswas
authors.affiliation: Department of Materials Engineering, Indian Institute of Science , Bangalore, India 560012.
authors.forename: Injamamul
authors.initials: I
authors.lastname: Arief
authors.affiliation: Department of Chemistry, National Institute of Technology , Durgapur, WB India 713209.
authors.forename: Sujit Sankar
authors.initials: SS
authors.lastname: Panja
authors.affiliation: Department of Materials Engineering, Indian Institute of Science , Bangalore, India 560012.
authors.forename: Suryasarathi
authors.identifier: http://orcid.org/0000-0001-8043-9192
authors.initials: S
authors.lastname: Bose
keywords: Conductivity; EMI shielding; Mechanical properties; Nanomaterials; Polymer blends