Electrochemical Characteristics of Coated and Uncoated Aluminium in 0.5 M H2SO4 Solution

The electrochemical corrosion behaviour of coated and uncoated Al samples were studied in 0.5 M H₂SO₄ using open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques. OCP measurement revealed that the coated Al exhibited lower susceptibility to dissolution in the electrolyte solution, compared with the uncoated Al. Based on EIS analysis; this barrier decreased the quantity of charge which can be stored in the Al/electrolyte interface, and increased the charge transfer resistance. Potentiodynamic polarization confirmed that the coating definitely increased the corrosion resistance of the Al sample by lowering both the cathodic and anodic half reactions in the acid solutions.