Electrochemical Modulation of the Thickness of Polypyrrole Films by Using Different Anionic Dopants

摘要

The tailoring of key characteristics of conducting polymers (e.g., thickness, conductivity, degree ofoxidation, color and morphology) is desirable for specific applications. We present results on theregulation of the thickness of polypyrrole films electrochemically grown on glassy carbon bypotentiodynamic and potentiostatic techniques at circumneutral pH in the presence of selected aqueous- - - - - 2- - dopant anions (i.e., I , NO3 , Br , Cl , ClO4 , SO4 and F ). In this manner, a supporting electrolytecontaining KI yields relatively thick and highly conductive films whereas KF produces littleconductive, very thin films. Other electrosynthesis parameters (i.e., applied potential range, number ofcycles, time) also play a key role. For example, one can obtain insulating films by applying potentialsin the region required for overoxidation of the film.