Electropolymerization of indole and study of electrochemical behavior of the polymer in aqueous solutions

Polyindole was obtained by electrochemical polymerization of the monomer on glassy carbon electrode in aqueous solutions. The electrochemical behavior and the electroactivity of film were studied by cyclic voltammetry under various conditions. Here, an attempt was made to find more suitable electrochemical polymerization conditions such as number of potential cycles, potential scan rate, switching potential, acid and monomer concentration. The influence of the temperature of synthesis on the oxidation peak current was studied. As the temperature of synthesis is raised the rate of polymer formation increases linearly with the temperature from 0 to 50 degrees C. The effect of the pH (buffer solutions) on the film response was also investigated. At pH > 7, there is practically no response. However, the film is not destroyed and its response is recovered in acidic solution. Mechanisms of the redox process and the inactivation of polyindole are also discussed. (C) 1998 Elsevier Science S.A. All rights reserved.