Magnetoresistive polyaniline–silicon carbide metacomposites: plasma frequency determination and high magnetic field sensitivity. Issue 29 (8th July 2016)

• Record Type: Journal Article
• Authors: Gu, Hongbo; Guo, Jiang; Khan, Mojammel Alam; Young, David P.; Shen, T. D.; Wei, Suying; Guo, Zhanhu
• Is Part Of: Physical chemistry chemical physics. Volume 18:Issue 29(2016)
• Page Start: 19536
• Page End: 19543
• Publication Date: 2016-07-08
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c6cp02694j
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Both negative permittivity and high magnetic field resistance sensitivity are observed in silicon carbide/polyaniline nanocomposites. Abstract : The Drude model modified by Debye relaxation time was introduced to determine the plasma frequency ( ω p ) in the surface initiated polymerization (SIP) synthesized β-silicon carbide (β-SiC)/polyaniline (PANI) metacomposites. The calculated plasma frequency for these metacomposites with different loadings of β-SiC nanoparticles was ranging from 6.11 × 10 4 to 1.53 × 10 5 rad s −1 . The relationship between the negative permittivity and plasma frequency indicates the existence of switching frequency, at which the permittivity was changed from negative to positive. More interestingly, the synthesized non-magnetic metacomposites, observed to follow the 3-dimensional (3-D) Mott variable range hopping (VRH) electrical conduction mechanism, demonstrated high positive magnetoresistance (MR) values of up to 57.48% and high MR sensitivity at low magnetic field regimes.