Experimental and Quantum Chemical Investigation of Corrosion Inhibitive Action of Sertraline on Mild Steel in Acidic Medium

An anti-depressant drug, Sertraline (SRT) in stereoisomeric form cis-(1S,4S)-SRT is examined for its corrosion inhibitive action on mild steel (MS) in 1 M HCl at the temperature range of 303 K -333 K with four hours of immersion. The drug is found to show satisfactory results of 93.3% at 50 ppm and 313 K, with the techniques of gravimetry, Potentiodynamic polarization and electrochemical impedance spectroscopy. Quantum chemical studies and optimized structure-supported HOMO and LUMO, verified the drug as an efficient inhibitor. The drug act on the MS surface with mixed type inhibitive mechanism and follows Langmuir adsorption isotherm. AFM has observed a reduction in average roughness of the metallic surface after the application of inhibitor, from 221 to 50 nm.