Electrochemical Capacitor Behavior of Polypyrrole Coated Mild Steel Electrodes

Polypyrrole (PPy) coatings have been deposited potentiodynamically on mild steel surface from 0.3 M aqueous oxalic acid solutions containing 0.1 M pyrrole. Cyclic voltammetry and electrochemical impedance spectroscopy techniques (EIS) were used to investigate the electrochemical properties of coatings in 0.3 M oxalic acid solutions. The performance of the capacitors was tested by using galvanostatic charge-discharge cycling within a potential range from 0.0 to 0.6 V. The maximum specific capacitance of PPy coated mild steel electrode is 8.57 x 10(3) F g(-1). The Pyy-coated mild steel system behaved like PAni and not as Ppy, exhibited high capacitance. It can be safely concluded the feasibility of the PPy coated mild steel electrode for use in electrochemical capacitor.