Electropolymerization kinetics of pyrrole in aqueous solution on graphite felt electrodes

Polypyrrole films doped with lithium perchlorate were electrogenerated on g raphite felt supporting electrodes by applying an anodic potential of 0.9 V versus Ag/Ag'. The kinetic parameters were calculated by means of ex situ microgravimetric and electrochemical data. The experimentally obtained kine tic equations were R-p.w = k(w)[E](0.55)[Mo](0.51) from the microgravimetri c data and R-p.c = k(c)[E](0.44)[Mo](0.50) from the values of the charge co nsumed during the electropolymerization process. Electrochemical parameters , such as the charge generated from the polymerization process (Q(pol)), th e charge storage efficiency (SE) and the doping level were also calculated. The results obtained suggest that the electrolyte plays an active role in the electropolymerization process, as well as the existence of secondary re actions simultaneous to the electropolymerization process. On the other han d, the charge storage efficiency and the doping level decreased inversely p roportionally to both the reaction time and the concentrations of the monom er and electrolyte. (C) 2001 Elsevier Science B.V. All rights reserved.