Electrochemical Properties of Polypyrrole Nanoparticles – The Role of Doping Ions and Synthesis Medium

Electrochemical properties of polypyrrole nanoparticles coated on glassy carbon electrodes were studied. The nanoparticles were obtained in a chemical polymerization step using a novel templateless procedure – oxidation of pyrrole released either from poly (n‐butyl acrylate) microspheres or from micelles of crosslinked alternating polymer (poly (maleic anhydride‐alt‐1‐octadecene)). Voltammetric measurements confirmed high ion transport rate inside the polymer and minor influence of the kind of doping ion and electrolyte ions present in the solution. However, electrochemical impedance spectroscopy measurements revealed a significant difference in the properties of polypyrrole nanoparticles, depending on the synthesis conditions. In case of polypyrrole synthesized in the presence of poly (n‐butyl acrylate) microspheres EIS spectra were almost independent of kind of electrolyte ions and doping anion, pointing to exposed bulk capacitive properties. On the other hand, polypyrrole nanoparticles obtained in the presence of alternating polymer micelles represent a typical constant phase element behavior with impedance significantly dependent on the kind of oxidizing (doping) anion. Due to their capacitive properties polypyrrole nanoparticles obtained in the presence of poly (n‐butyl acrylate) microspheres were applied as solid contacts in ion‐selective electrodes.