Electrochemical data of single and hybrid sol–gel coating precursors for aluminum alloy corrosion protection in 3.5% NaCl

The anti-corrosion performances of single(TEOS) and hybrid (APTES-TEOS) sol–gel coatings on Al alloy samples exposed to 3.5 wt% NaCl were evaluated employing electrochemical techniques such as electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The data acquired using the three corrosion analysis techniques were in accordance with each other where hybrid sol–gel coating offered the lowest corrosion rate and current density in comparison to the single precursor silanol coating. Tafel curves suggested that the hybrid silane coatings mitigate both the anodic and cathodic reactions simultaneously (mixed type inhibitor). These techniques justified that incorporation of hybrid sol–gel improved the Al corrosion protection performance considerably.