The effect of pH on the pyrrole electropolymerization on iron in malate aqueous solutions

The influence of pH on pyrrole electropolymerization on iron surfaces in malate aqueous medium was analyzed using different electrochemical techniques. The sodium sulfate solution was used as reference.Homogeneous and adherent PPy films were obtained at pH between 4 and 7 in 0.2 M malic and 0.5 M pyrrole solution by potentiostatic mode, while the PPy coatings obtained from sulfate aqueous solutions in the same range of pH are non-adherents significantly.SEM analysis showed that PPy structure depends closely on the electrochemical conditions. FT-IR analysis confirms that PPy coatings have the same structure as those obtained on Pt electrodes.