Electrochemical quartz crystal microbalance studies on the two reduction processes of conducting polypyrrole nitrate films in aqueous solutions

The mechanism of the two reduction processes of polypyrrole nitrate (PPy (NO3−)) film in aqueous solutions was studied by electrochemical quartz crystal microbalance measurements. It was verified that the reduction of PPy (NO3−) film in an acidic aqueous solution is accompanied with counter-anion dedoping. In a neutral aqueous solution, the counter-anion dedoping occurs in the first reduction process and hydrated cation insertion takes place in the second reduction process of the PPy(NO3−) film.