Shot Noise Analysis to Investigate the Corrosion Inhibition of AZ91D Magnesium Alloy in Sulfuric Acid Solution

The corrosion inhibition of AZ91D magnesium alloy in 0.01 M H2SO4 by a Schiff base compound was investigated using Potentiodynamic polarization, Electrochemical Impedance Spectroscopy and Electrochemical Noise methods. It is found that the Schiff base acts as mixed-type inhibitor and the inhibition efficiency increases with concentration. Electrochemical impedance spectroscopy results showed that the Schiff base acts by adsorption at the metal/solution interface. Shot noise analysis showed that the inhibitor addition decreases the number of charge transfer events instead of the value of charge transfer at each electrochemical corrosion event. The corrosion inhibition effect was approved by suitable surface analysis.