Inhibition by Ginkgo leaves extract of the corrosion of steel in HCl and H2SO4 solutions

The inhibition effect of Ginkgo leaves extract (GLE) on the corrosion of cold rolled steel (CRS) in 1.0–5.0 M HCl and 0.5–2.5 M H2SO4 solutions was investigated for the first time by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. The results show that GLE is a good inhibitor, and exhibits more efficient in 1.0 M HCl than 0.5 M H2SO4. The adsorption of GLE on CRS surface obeys Langmuir adsorption isotherm. GLE acts as a mixed-type inhibitor in 1.0 M HCl, while a cathodic inhibitor in 0.5 M H2SO4.

► Ginkgo leaves extract (GLE) acts as a good inhibitor for steel in HCl and H2SO4 media.
► The inhibition efficiency follows the order: HCl > H2SO4.
► The adsorption of GLE on steel surface obeys Langmuir adsorption isotherm.
► GLE behaves as a mixed-type inhibitor in 1.0 M HCl, while cathodic inhibitor in 0.5 M H2SO4.