Polymer Acid Doped Polyaniline Is Electrochemically Stable Beyond pH 9

We report the pH dependence of the electrochemical redox behavior of polyaniline (PANI) that is template synthesized with poly(2-acrylamido-2-methyl-1-propanesulfonic acid), PAAMPSA. Cyclic voltammetry and spectroelectrochemistry were used to assess the oxidation and protonation states of PANI−PAAMPSA. Stable and reversible pernigraniline−emeraldine−leucoemeraldine transitions extend beyond pH 7. Direct pernigraniline−leucoemeraldine transitions dominate in alkaline conditions; these transitions are stable and reversible between 7 and 10, extending the pH stability of PANI well beyond those previously reported.