Electrosynthesis of Polyaniline-TiO2 Nanocomposite Films on Aluminum Alloy 3004 Surface and its Corrosion Protection Performance

The direct synthesis of polyaniline-TiO2 nanocomposite coatings on aluminum alloy 3004 (AA3004) surface has been investigated by using the galvanostatic method. The synthesized coatings were characterized by FT-IR, SEM-EDX, SEM and AFM. Optical absorption spectroscopy reveals the formation of the emeraldine oxidation state form of polyaniline-TiO2 nanocomposite. The corrosion performances of polyaniline-TiO2 nanocomposite coatings were investigated in 3.5% NaCl solution by Tafel polarization and Electrochemical Impedance Spectroscopy (EIS) methods. The corrosion rate of polyaniline-TiO2 nanocomposite coating on AA3004 was found ∼260 times lower than bare AA3004 and corrosion potentials of these coatings have shifted to more positive potentials (105 mV). The results of this study clearly ascertain that the polyaniline-TiO2 nanocomposite coating has outstanding potential to protect the AA3004 against corrosion in a chloride environment.