INFLUENCE OF THE DOPED COUNTERANIONS ON THE PENETRATION OF H-METHYLPYRROLE)( CATIONS THROUGH POLY(N)

The reduction of H+ cations on the Pt electrode coated with poly(N-met hylpyrrole) (PNMP) film was studied in an acidic aqueous solution. The reduction depends strongly on the counteranions originally doped in P NMP during polymerization. H+ cations can penetrate the neutral or ove roxidized film from PNMP(TsO(-)), in which the H+ diffusion coefficien t is estimated as 10(-5) cm(2) s(-1) by the potential step chronoamper ometry method. But the neutral or overoxidized film from PNMP(NO3-) is closed for H- penetration. (C) 1996 John Wiley & Sons, Inc.