Charge transfer across a conducting polypyrrole membrane separated by two electrolyte solutions

This article describes anion transfer across a conducting polypyrrole membrane (PPM) using cyclic voltammetry with a four‐electrode system. The transfer process of both chloride and nitrate anions across the polypyrrole membrane used to separate two pools of electrolyte solutions has been studied. A wide potential window beyond 3 V was obtained, and well‐developed voltammograms for the transfer of nitrate and chloride anions appeared within this window. The transfer process depends on the ion size, the ion charge, and the surface characteristics of the polypyrrole membrane. The one‐way transfer phenomenon observed in different potential‐bias directions can be explained by the asymmetrical ion channel model of the polypyrrole membrane.