Ascorbic acid as corrosion inhibitor for Q235 mild steel in acidic environments

The inhibition effect of ascorbic acid (AA) on mild steel corrosion in 1 M HCl and 0.5 M H2SO4 was estimated using electrochemical and surface probe techniques. Potentiodynamic polarization results showed AA to be a mixed type inhibitor in both acidic environments, whereas the impedance results revealed adsorption of the AA species on the steel surface. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) studies revealed the formation of a protective film adsorbed AA on the steel surface. Quantum chemical calculations were used to confirm the ability of AA to adsorb on a steel surface.