6533b7d9fe1ef96bd126d57c

RESEARCH PRODUCT

Towards a deeper understanding of the inhibition mechanism of a new 1,2,3-triazole derivative for mild steel corrosion in the hydrochloric acid solution using coupled experimental and theoretical methods

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Abstract The corrosion inhibition effect of a new synthesized heterocycle 1,2,3-triazole, namely(1-p-tolyl-1H-1,2,3-triazol-4-yl) methanol (TTM) was studied in 1 M hydrochloric acid solution by using both experimental and theoretical techniques. The inhibitory action of the TTM was investigated by potentiodynamic polarization (PDP) at various temperatures (298–333 K). PDP experiments revealed that the TTM behaved as mixed type inhibitor by decreasing both anodic and cathodic corrosion densities. Electrochemical impedance spectroscopy (EIS) measurements confirmed that the studied inhibitor can suppress mild steel corrosion effectively in acidic solution with an inhibition efficiency of 90% after 60 min of immersion. The adsorption of the TTM compound on the mild steel surface was found to follow the Langmuir and El-Awady thermodynamic-kinetic models. The changes in contact angles from 80° to 102° identified the generation of an adsorbed protective layer which is confirmed by SEM/EDX investigation and FT-IR spectroscopy. Additional insights on the most reactive areas in terms of donor/acceptor interactions were derived using DFT based quantum chemical calculations for neutral as well as protonated forms of TTM. Molecular dynamics simulations (MD) have been adopted to shed light on the mechanism of molecular adsorption. The interactions between TTM and Fe-atoms were characterized with the aid of reduced density gradient (RDG); vdW interaction seems to be the dominative regime of TTM- Fe atoms in the hydrochloric acid solution. Under dynamic mode, TTM protects the mild steel against corrosion by constraining the diffusion of corrosive ions (H2O, H3O+, Cl−) present on its surface. Electron localization function (ELF), Fractional free volume (FFV) are used as powerful tool to provide a better theoretical scenario for understanding the mode of adsorption on the surface of Mild steel (MS).