VARIABLE CAPACITANCE AND CONDUCTANCE IN POLYANILINE - A SIMPLE-MODEL WITH INTERACTING SITES AND A SINGLE QUASI-REVERSIBLE CHARGE-TRANSFER

This study is devoted to the comparison of Cyclic Linear Sweep Voltammetry curves obtained for an electronic conducting polymer, the polyaniline, and curves obtained from a mathematical model. Our model is based on the following assumptions: - reversible, quasi-reversible or irreversible charge transfer - electrostatic or mechanical interactions within the electroactive polymer in order to explain the abnormal width of voltammetric peak of these materials [1-3] - variable capacitance to explain the polymer's capacitive behaviour [4] - variable conductivity to explain the shape of the voltammograms of such polymer [5-7] - Steady-state hysteresis which is taken into account by different values for the formal redox potential between forward and reverse scans, together with a slight dependence of the conductivity with the current direction.