Inhibiting effect of 5-(chloromethyl)quinolin-8-ol Hydrochloride (QIN1) on carbon steel corrosion (CS) in 1.0 M HCl solution was investigated by electrochemical impedance spectroscopy and potentiodynamic measurements at 303-333 K in the presence of different concentrations of QIN1 ranging from 10-3M to 10-6M. Potentiodynamic polarization study clearly revealed that compound acted as mixed type inhibitor. Further, the quantum chemical calculations using density functional theory (DFT) gave a profound insight into the inhibition action mechanism of QIN1 and their calculation parameters such as EHOMO, ELUMO and ΔE are corroborative with the results of experimental studies. The various thermodynamic parameters of dissolution processes were evaluated in order to elaborate adsorption mechanism. Adsorption of inhibitor obeyed Langmuir adsorption isotherm model.
