Dielectric and AC Conductivity Studies in PPy-Ag Nanocomposites

Abstract

Polypyrrole and silver nanoparticles have been synthesized at 277 K by chemical route. Nanoparticles of polypyrrole-silver (PPy-Ag) composites were prepared by mixing polypyrrole and silver nanoparticles in different weight percentages. Dielectric properties as a function of temperature in the range from 300 K to 550 K and frequency in the range from 50 Hz to 1 MHz have been measured. Dielectric constant decreased with increase in frequency and temperature. Dielectric loss decreased with increase in frequency and increased with increase in temperature. Using dielectric data AC conductivity has been determined. Conductivity was found to be in the order of 10 −3 (Ω −1 m −1 ) and it increased with increase in temperature. Temperature variation of conductivity data has been analyzed in the light of Mott's polaron hopping model. Activation energy for conduction has been determined. Activation energy was determined to be in the order of meV and it has increased with increase in frequency and Ag nanoparticles content. This is the first time that PPy-Ag nanocomposites have been investigated for dielectric properties and AC conductivity and data analyzed thoroughly.

Morphological, Optical, Electrical Characterizations and Anti- Escherichia coli Bacterial Efficiency (AECBE) of PVA/PAAm/PEO Polymer Blend Doped with Silver NPs;

“…The figure demonstrates that this activity can be assigned to the interfacial polarization of the A.C electrical conductivity that increases as the frequency rises. As Ag NPs increase, electrical conductivity increases, which is also due to an increase in the density of the charge carrier in the polymer blend [41].…”

Ac Conductivity and Dielectric Studies of Polypyrrole Copper Zinc Iron Oxide Nanocomposites

“…The decrease in dielectric loss є′′ with frequency can be attributed to the fact that, at low frequencies, the value of є′′ is due to the free charge motion within the materials. At moderate frequencies є′′ is due to contribution of ion jumps, conduction loss of ion migration and ion's polarization loss, At high frequencies, the vibration of ions may be the only source of loss and hence dielectric loss has minimum value [13]. On addition of nanoparticles increase in the lower frequency region reflect the enhancement of mobility of charge carrier, with rise in frequency in low frequency region DOI: 10.9790/4861-0805028390 www.iosrjournals.org 87 | Page followed by a peak in the loss spectra.…”

Dielectric properties and ac conductivity of CuO and Fe2O3 doped polycarbazole nanocomposites

“…The straight lines were fit to the conductivity data and slope of these linear fits have been used to estimate activation energy Ea. The Ea increases with increase in wt% of dopants it may be due to grain boundary scattering of polarons [33]. Figure.…”

“…The σac increased with frequency and it is due to dipoles inside the samples being rotated with the frequency of applied field and dielectric relaxation caused by polar bands. Both PCz and composites exhibited semiconducting nature as their conductivity increased with increase of temperature similar to the reports [29,32,33]. Figure .3.…”