0000000000515170
AUTHOR
J. Vilaplana
Electrochemical behaviour and electrical percolation in graphite-epoxy electrodes
The electrochemical properties of mouldable graphite-epoxy composite electrodes have been studied as a function of graphite content. The shape of ferri-ferrocyanide voltammograms relates to the ratio of graphite and an adsorption process. The dielectric constant from spectroelectrochemical impedance measurement of this composite electrode is maximum when the proportion of graphite is ca. 60 wt%. An electrochemical equivalent circuit is proposed. The graphite-epoxy composite acts as a multi-microelectrode near this proportion.
Prussian blue films deposited on graphite+epoxy composite electrodes: electrochemical detection of the second percolation threshold
Abstract The electrochemical behavior of Prussian blue films galvanostatically electrodeposited on graphite+epoxy-resin composite electrodes was studied. The composite electrodes were prepared with different graphite proportions and their effect on electrochemical reduction of the Prussian blue was analyzed by means of the uncompensated resistance approximation and the electrical percolation theory. The results suggest that the electrode with 60% graphite reaches the second percolation threshold and its internal structure changes from a compact to a porous one. Mechanical tensile tests were performed in order to confirm the critical behavior of this material at the percolation thresholds. T…