Polypyrrole nanoparticles of high electroactivity. Simple synthesis methods and studies on electrochemical properties

Two alternative simple and templateless procedures for synthesis of polypyrrole nanoparticles are described, with oxidation of pyrrole monomer either by iron(III) toluenesulfonate or potassium hexacyanoferrate(III), in presence of either alternating polymers micelles or poly(vinyl alcohol) as only dispersing medium. As confirmed by TEM pictures nanoparticles of uniform size close to 60 nm were obtained. Electrochemical properties of obtained nanoparticles, drop cast to form films on electrodes were studied using different techniques. It was shown that these layers were characterized by high electroactivity, fast ion exchange and almost capacitive properties in the oxidized state. These properties result from loosely packed structure of hydrophilic nanoparticles in the layer, surrounded by electrolyte solution. Although typically relatively immobile doping anions were used, they were easily released from the polymer assuring anion-exchange properties. The simplicity of the described synthesis procedures and high electroactivity of obtained nanoparticles is promising from the point of view of their possible applications.