Abstract
Corrosion inhibition effect of Verbena extract (VE) on C38 steel in 1 M HCl medium was investigated for the first time by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. Inhibition efficiency of 85.3% was achieved with 6g/L VE at 298K. The polarization studies showed that VE acts as mixed-type inhibitor. The Nyquist plots showed that on increasing VE concentration, increases charge transfer resistance and decreases double layer capacitance. VE obeys the Langmuir adsorption isotherm.