Electrosynthesis, Characterization and Corrosion Inhibition Study of DBSA-doped Polyaniline Coating on 310 Stainless Steel

Abstract

<em>The synthesis of polyaniline </em><em>doped with dodecylbenzene sulphonic acid (Pani-DBSA) </em><em>coatings on</em><em> 310 stainless steel (310 SS) </em><em>surfaces has been investigated by using the galvanostatic method. The synthesized coatings were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible absorption spectrometry and Scanning Electron Microscopy (SEM).The anticorrosion performances of </em><em>Pani-DBSA</em><em> coatings were investigated </em><em>in </em><em>5% NaCl </em><em>solution</em><em> by the potentiodynamic polarization technique and Electrochemical Impedance Spectroscopy (EIS). The corrosion rate of </em><em>Pani-DBSA</em><em> coated 310 SS was found </em><em>∼</em><em>30 times lower than bare 310 SS</em><em>and potential corrosion increased from -0.84 V versus Ag/AgCl for uncoated 310 SS to -0.71 V versus</em><em> Ag/AgCl for </em><em>Pani-DBSA</em><em> coated 310 SS electrodes. Electrochemical measurements indicate that </em><em>Pani-DBSA</em><em> coated have good inhibiting properties with a mean efficiency of ~96% at 5 mA cm</em><em>^-2</em><em> current density applied to 310 SS corrosion in chloride media. The results of this study clearly ascertain that the</em> <em>Pani-DBSA</em><em> has an outstanding potential to protect 310 SS against corrosion in a chloride environment.</em>