A Green and Sustainable Approach for Mild Steel Acidic Corrosion Inhibition Using Leaves Extract: Experimental and DFT Studies

Abstract: The effect of Holoptelea integrifolia leaf extract (HILE) on corrosive dissolution of mild steel in 1 M hydrochloric acid was investigated using weight loss, surface, electrochemical, and DFT methods. Results showed that corrosion protection capability of HILE increases with increasing its concentration and maximum value of 93.91% was attained at 400 mg/L concentration. Adsorption of phytochemicals present in HILE on metallic surface followed the Langmuir adsorption isotherm. Tafel polarization study revealed that HILE acts as mixed type inhibitor. EIS study revealed that HILE inhibits mild steel corrosion by getting adhered on the mild steel surface. SEM and AFM analyses showed that in presence of HILE, metallic surface becomes smooth because of the formation of inhibitive film over metallic surface. DFT calculations were also performed on the several active phytochemicals. It was found that β-amyrin was the most effective phytochemical for mild steel corrosion among the available constituents present in the extract. Graphical Abstract: [Figure not available: see fulltext.]. © 2018, Springer International Publishing AG, part of Springer Nature.