Sustainable and Green Corrosion Inhibition of Mild Steel: Insights from Electrochemical and Computational Approaches

Abstract

Natural and fragrant compounds, essential oils (EOs) extracted from plants through hydrodistillation, are gaining popularity as eco-friendly and sustainable agents to protect metals and alloys from corrosion in acidic environments. This research focused on extracting and characterizing an EO obtained from the Cuminum cyminum (CC) plant native to India. The study aimed to evaluate the inhibitory properties of this EO on mild steel in a 0.5 M HCl solution at different concentrations. Various analytical techniques, including potentiodynamic polarization curves, electrochemical impedance spectroscopy, optical microscopy, infrared spectroscopy, and proton magnetic resonance, were employed to assess the effectiveness of this EO extract. Our findings indicate that the Cuminum cyminum L (CCL) extract effectively reduces the corrosion of mild steel in hydrochloric acid with an inhibition efficiency ranging from 79.69 to 98.76%. The optimal inhibition concentration was 2 g/L of EO, and surface analysis confirmed the formation of a protective layer. Furthermore, our results suggest that the inhibitor binds to the metal surface through a charge-transfer process, creating a protective film. Finally, we utilized theoretical calculations and molecular dynamics simulations to elucidate the inhibition mechanism on both a global and local scale.

Cuminum Cyminum (Jeera) as a Green Corrosion Inhibitor -a Review

“…Metals: Various metals have been used in corrosion inhibition study such as Al [19][20][21][22], Brass [23], Copper [24], MS [25,26,27,28], CS [29], S-300 steel [30], and Zn [31,32].…”

“…Solvents: Solvents like Distilled water [19,20,22], Double distilled water [23-26, 29, 30,32], Diethyl ether [28], Methanol [21] and Ethanol [30] were used to prepare plant extract.…”

“…Corrosion inhibition is due to formation of protective film formed on the metal surface. Film formed on metal surface were studied by various techniques, like SEM [20,23,28,29,31], FT-IR spectroscopy [25,[28][29][30][31] and UV-Vis. spectroscopy [25,26].…”

“…Other techniques: OCP [24,27,31,32], QCC [26], ENA [24,27], LPR [26], OM [28], PMR [28], MDS [28] and Fluorescence [25] were also used.…”