Electrochemical properties of pyrrole/aniline polymer composite

Bi-polymer film electrodes of polypyrrole (ppy) and polyaniline (pan) were prepared by electrochemical implantation into porous ppy matrix with pan as level of 10 to 35% in order to improve the electrical properties. The rate constants of electropolymerization reactions were measured with smooth Pt, Pt covered with ppy (Pt/ppy), and Pt covered with pan (Pt/pan) of modified rotating disk electrode. The electropolymerization rate of pan polymer was faster on the Pt/ppy electrode as 2.67 x 10(-5) cms(-1) by a factor of hundred than 2.30 x 10(-7) cms(-1) of the Pt/pan. Cyclic voltammograms of Pt/ppy/pan(x) electrodes were quite different with the doping ions which were ClO4- and PF6-. The characteristic properties of redox reaction were more obvious at doped with PF6- ion. The amount of pan in the ppy matrix enhanced the doping level of the electrode to 52% at pan content (x) of 0.2, doping/undoping efficiency to 88%, and the conductivity of the ppy/pan was 331 Scm(-1) at x= 0.35. However the cyclability was reduced by 75%, relative to ppy alone.