2-Aminobenzothiazole as an efficient corrosion inhibitor of AA6061-T6 in 0.5 M HCl medium: electrochemical, surface morphological, and theoretical study

The inhibitive action of 2-aminobenzothiazole (ABT) on the corrosion of AA6061-T6 was evaluated in 0.5 M HCl by electrochemical techniques. The electrochemical results were validated by theoretical calculations using density functional theory (DFT). ABT showed a mixed inhibitor behaviour with 71–90% inhibition efficiency in the 1 × 10⁻⁴ to 1 × 10⁻³ M concentration range and at 303 to 323 K temperature. The inhibition power of ABT increases with its concentration and rise in the temperature of the medium. The polarization results showed a reduction in corrosion rate and improvement in inhibition performance on increasing ABT concentrations, which reveal the ABT's adsorption on the alloy. The evaluation of kinetic and thermodynamic results revealed that ABT inhibits the AA6061-T6 corrosion by mixed adsorption, following the Langmuir isotherm model. The observed increase in polarization resistance with increased ABT concentrations indicates the attenuation of AA6061-T6 deterioration. Furthermore, the corroded and inhibited specimen's surface scanning is performed to confirm the ABT's adsorption on the alloy sample by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Graphical abstract: [Figure not available: see fulltext.]