Correlation of carrier localization with relaxation time distribution and electrical conductivity relaxation in silver-nanoparticle-embedded moderately doped polypyrrole nanostructures
1 Department of Physics, University of Kalyani, Kalyani - Nadia-741235, West Bengal, India
2 Department of Chemistry, P. D. Women's College - Jalpaiguri-735101, West Bengal, India
Received: 28 October 2013
Accepted: 21 January 2014
The electrical conductivity relaxation in moderately doped polypyrrole and its nanocomposites reinforced with different proportion of silver nanoparticles was investigated in both frequency and time domain. An analytical distribution function of relaxation times is constructed from the results obtained in the frequency domain formalism and is used to evaluate the Kohlrausch-Williams-Watts (KWW) type decay function in the time domain. The thermal evolution of different relaxation parameters was analyzed. The temperature-dependent dc electrical conductivity, estimated from the average conductivity relaxation time is observed to depend strongly on the nanoparticle loading and follows Mott three-dimensional variable range hopping (VRH) conduction mechanism. The extent of charge carrier localization calculated from the VRH mechanism is well correlated to the evidences obtained from the structural characterizations of different nanostructured samples.
PACS: 77.22.Gm – Dielectric loss and relaxation / 73.22.-f – Electronic structure of nanoscale materials and related systems / 72.80.Le – Polymers; organic compounds (including organic semiconductors)
© EPLA, 2014