Application of Butea monosperma (Palasha) Leaves Extract as Green Corrosion Inhibitor for Mild Steel in Hydrochloric Acid Solution: A Theoretical and Electrochemical Approach

摘要

The inhibition effect of Palasha (Butea monosperma) leaves extract on mild steel in 1M HCl wasinvestigated using gravimetric, potentiodynamic polarization and electrochemical impedancespectroscopy. Potentiodynamic polarization results revealed that the studied extract is a mixed-typeinhibitor. The inhibition efficiency increased up to 96% at 300 ppm. The Rct of inhibited systemincreased and double layer capacitance Cdl decreased with increasing inhibitor concentration. UV- Visible spectroscopic investigation of inhibited system suggested a complexation between the activemolecules of extract and the metal surface atoms. Quantum chemical calculations supported theadsorption of inhibitor molecules onto the metal surface.