Greener method for high-quality polypyrrole

Conducting polypyrrole has been synthesized via a simple metal catalyzed process. The oxidative polymerization of pyrrole using hydrogen peroxide and a catalytic amount of iron(III) in an acidified aqueous medium afforded conducting polypyrrole in very good yield. The copper(II) or cerium(IV) catalyzed reactions under similar conditions gave poor yields. The iron(III) catalyzed reaction carried out in the absence of the acid produced low-quality polypyrrole that contain hydroxyl and carbonyl groups resulting from the nucleophilic attack of water or hydroxyl radicals.