Influence of Process Parameters on the Conductivity and Surface Morphology of Polypyrrole Films

摘要

Influence of electrochemical process parameters such as monomer and electrolyte concentrations,current density,pH of the electrolyte,and type of electrolyte have been studied during polymerization of polypyrrole (Ppy).The changes in the conductivity of synthesized Ppy film for different electrolytes were observed by chrono-potentiograms recorded during the electrochemical polymerization and it was confirmed by measuring it using four probe techniques.It was found that the electrochemical process parameters have a considerable influence on the conductivity of the film.The Ppy film was synthesized on a platinum substrate by electrochemical polymerization with different electrolytes such as potassium nitrate,sodium nitrate,sulphuric acid,hydrochloric acid,potassium chloride,sodium chloride,oxalic acid,and sodium salicylate,under galvanostatic condition over a wide range of pH of the reaction medium and applied current density.The different concentration ratios of pyrrole and sodium nitrate were considered during synthesis of Ppy films.It has been observed that the polymerization potential increases with the pH and applied current density.One could synthesize Ppy film with very good surface morphology and conductivity with optimized process parameters.The characterization of synthesized Ppy film was done by electrochemical technique,electrical conductivity,Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM).