Potential role of a novel green eco-friendly inhibitor in corrosion inhibition of mild steel in HC1 solution: Detailed macro/micro-scale experimental and computational explorations

摘要

Ziziphora leaves extract was utilized as a new eco-friendly green inhibitor for acidic-induced corrosion of mild steel (MS). The inhibition activity of various phytochemicals present in the Ziziphora leaves aqueous extract, e.g., acacetin, chrysin, and thymonin were probed by electrochemical examinations. The influence of Ziziphora leaves extract on HCl aggressiveness reduction was inspected via several surface experiments. Moreover, the structure of extract phytochemicals was characterized by Fourier transform infrared spectroscopy (FT-IR) spectroscopy and ultraviolet-visible (UV-Vis) spectroscopy. The electrochemical impedance spectroscopy (EIS) analysis evidences that by increasing the concentration of Ziziphora leaves extract (up to 800 ppm) the inhibition performance raises to 93% (after 2.5 h). The polarization curves reveals that through mixed inhibition control the corrosion of steel was retarded by Ziziphora leaves extract. The surface studies ensure the Ziziphora leaves extract effectiveness in MS surface damage/roughness reduction. Also, the Ziziphora leaves extract molecules adsorption on the steel surface occurs according to the Langmuir isotherm model. Alongside experimental explorations, theoretical tools including classical simulations (molecular dynamics, MD connected with Mote Carlo, MC) and quantum chemical computations (density functional theory, DFT) were chosen for obtaining basic electronic/atomic-scale details about the extract compounds adsorption on target metal and their active sites. The results of molecular simulations the adsorption tendency of green extract molecules on the steel, which supports the experimental outcomes. (C) 2020 Elsevier Ltd. All rights reserved.