PREPARATION AND PHYSICAL AND ELECTRICAL CHARACTERISATION OF NOVEL CARBON NANOTUBE MICROELECTRODES

This work reports on an earnest effort of preparing novel carbon nanotube and graphite flake microelectrodes. Polyvinyldine Flouride (PVDF) was used as the polymer to fabricate the nanocomposite. The first work premise consists of the determination of percolation threshold for the carbon nanotubes (CNTs) and graphite filled nanocomposites. We obtained a percolation threshold of 1% and 18% with conductivity of 3.16 S/m and 1.05 S/m respectively, for the CNTs and graphite filled nanocomposites. The second premise deals with changing the sonication time, heat treatment, types of CNTs and average molecular weight of the PVDF to optimize the conductivity of the nanocomposites. Sonication time seems to be an important procedure to enhance the electrical conductivity. Besides it could also contribute to the dispersion of the fillers behaving as an individual microelectrode. The third premise was devoted to the construction of 10% and 25% of CNTs and graphite, respectively, as the microelectrodes in the nanocomposite. Preliminary experimental results of cyclic voltammetry show an increase in the current after 20 hours toluene etching at room temperature. It could be mentioned that the carbon nanotube fillers gave a hemispherical field indicating a microelectrode-like behaviour