Inhibition potential of Salsola oppositifolia extract as a green corrosion inhibitor of mild steel in an acidic solution

This article investigates the inhibitory efficiency of a green corrosion inhibitor obtained from Salsola oppositifolia (SO) extract in acidic solutions.The extract was prepared from the aboveground and annual green leaves of SO with methyl alcohol.A Fourier Transform Infrared (FTIR) analysis of the extract revealed that it contains various functional groups and organic compounds that inhibit corrosion.FTIR analysis confirmed the presence of functional groups such as -OH, C=O, -COOH, and aromatic rings from flavonoids and alkaloids.These functional groups can coordinate with the metal surface via lone pair electrons and -bond interactions, forming a protective layer that impedes charge transfer processes.The inhibitory efficiency of mild steel in 0.5 HNO3 was studied at temperatures of 303-323 K by gravimetric and electrochemical methods and at concentrations of 50 mg/L, 75 mg/L, 100 mg/L and 150 mg/L.According to the results of the study, the inhibition efficiency increased with increasing inhibitor concentration, which was 91.85% at a concentration of 150 mg/L.Potentiodynamic polarization results indicated that the SO extract functions as a mixed-type corrosion inhibitor.The steel surface morphology upon adsorption of this green corrosion inhibitor was studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM).