Improved electromagnetic shielding behaviour of graphene encapsulated polypyrrole-graphene nanocomposite in X-band. (26th May 2020)

• Record Type: Journal Article
• Authors: Gill, Nisha; Gupta, Vinay; Tomar, Monika; Sharma, Amit L.; Pandey, O.P.; Singh, Dwijendra P.
• Is Part Of: Composites science and technology. Volume 192(2020)
• Publication Date: 2020-05-26
• Subjects: Nanocomposites -- Graphene -- Interfacial polarization -- Electromagnetic interference shielding; Composite materials -- Periodicals; Composite materials; Fibrous composites; Periodicals; 620.118
• DOI: 10.1016/j.compscitech.2020.108113
• Languages: English
• ISSNs: 0266-3538

Abstract

Abstract: The graphene encapsulated polypyrrole-graphene nanocomposites containing 0 to 0.2 wt% of graphene have been synthesized through in-situ chemical oxidative polymerization method. The electromagnetic shielding and dielectric behaviour of nanocomposite have been investigated in X-band (8.2–12.4 GHz) of microwave region. Nanocomposite containing 0.2 wt% of graphene (PG2) possess maximum shielding effectiveness due to absorption (SEA ) ~ 33 dB and least due to reflection (SER ) ≪ 1 dB in X-band. PG2 nanocomposite also has minimum skin depth ~250 μm (a criteria to decide the thickness of material for microwave application) and maximum attenuation constant. Enhanced microwave absorption and extremely suppressed reflection is attributed to increased dielectric loss. Increased dielectric loss is ascribed to formation of multiple interfaces, interfacial polarization, and formation of conducting pathways due to encapsulation of graphene in polypyrrole-graphene nanocomposites. The material exhibiting increased absorption and decreased reflection could be useful for many important applications such as stealth technology in aerospace, microwave communications, and checking of electromagnetic pollution. Highlights: Polypyrrole-graphene (PG) nanocomposite has been synthesized via in-situ chemical oxidative polymerization method. PG nanocomposite shows maximum microwave absorption of ~33 dB with least reflection ≪ 1 dB in X-band. The enhanced microwave absorption is caused by interfacial polarization due to the formation of multiple interfaces.