Electrochemical Characterization of a Polypyrrole/Montmorillonite Nanocomposite

The electrochemical activities of films prepared from chemically synthesized polypyrrole and a polypyrrole/ montmonrillonite nanocomposite are examined using cyclic voltammetry and chronopotentiometry. The nanocomposite exhibits redox chemistry at potentials ( V p , c = − 1500 , V p , a = − 1100 mV ) approximately 1 V more negative than in native polypyrrole. Chronopotentiometric studies show that the capacities of these two materials, when evaluated in terms of mass of polymer are similar and that the charge/discharge plateaus are also shifted by approximately 1 V. Two models are proposed to explain these results, one based on the inductive effect of the encasing anionic sheets, and one on a redox mechanism involving cation insertion.