Investigation of dielectric relaxation phenomena and AC electrical conductivity in graphite/carbon nanotubes/engine oil nanofluids (original) (raw)
Journal of Reinforced Plastics and Composites
Abstract
In this paper, we report an investigation on electrical conduction mechanisms of nanofluids based on commercial engine oil loaded with graphite (Gt) and multiwalled carbon nanotubes, at different concentrations. The impedance spectroscopy technique was used to measure the resistance and capacity characterizing each sample in a frequency range 100 Hz–1 MHz and a temperature range 300–400 K. Two formalisms were used to analyze the data: (a) the electrical conductivity which has found to follow the Jonscher’s law with single and double exponents for carbon nanotube concentrations below and above the percolation threshold, respectively, and (b) the complex impedance that has permitted to identify the relaxation peaks according to the Cole–Cole model. Both the two formalisms showed that when the carbon nanotube concentration is higher than the percolation threshold, a positive temperature coefficient and a remarkable change in conductivity were observed, suggesting that the presence of t...
Mohamed EL Hasnaoui hasn't uploaded this paper.
Let Mohamed know you want this paper to be uploaded.
Ask for this paper to be uploaded.