Protonation and doping behavior of polypyrrole films and powders

The differences in protonation and charge transfer behavior between polypyrrole(PPY) powders and films doped with inorganic acids, or bulky acids, were assessed quantitatively by the X-ray photoelectron spectroscopic (XPS) technique. PPY-dodecylsulfate and PPY-toluene-4-sulfonate films with [N+]/[N] ratio over 40% can be readily prepared electrochemically. Treatment of these salt films with a base results in the 25% deprotonated PPY. UV-visible light spectroscopy shows little difference in structures of PPY formed chemically and electrochemically.