The influence of electrochemical process parameters on the conductivity of poly(N-methylpyrrole) films by galvanostatic method

The influence of electrochemical process parameters viz. type of electrolyte, electrolyte concentration and current density have been studied during polymerization of poly(N-methylpyrrole) (P(NMP)). The changes in the conductivity of synthesized P(NMP) film for different electrolytes were noticed by chronopotentiograms recorded during the electrochemical polymerization and it was confirmed by measuring it using two probe technique. The current density used during the polymerization has a considerable influence on the conductivity of the film. The P(NMP) film was synthesized on the platinum substrate by electrochemical polymerization with different electrolytes such as potassium nitrate, sodium nitrate, nitric acid, oxalic acid, sodium salicylate, hydrochloric acid, potassium chloride, and sodium chloride under galvanostatic condition over a wide range of pH of the reaction medium and applied current density. The concentration ratio of N-methylpyrrole (NMP) and sodium nitrate were taken as 0.02 : 0.1, 0.05 : 0.05 and 0.1 : 0.02 respectively. It has been observed that, the polymerization potential increases with the pH and applied current density. A good quality P(NMP) film was formed by controlling the electrochemical process parameters. The characterization of synthesized P(NMP) film was done by electrochemical techniques, solubility test, FTIR and the scanning electron micrograph (SEM).