Improved performance of a new benzothiazole derivative in the inhibition of corrosion of carbon steel in a sulfuric acid medium

This research investigates the efficacy of a new benzothiazole derivative (BTFI) as a corrosion inhibitor for carbon steel in a 0.5 M H2SO4 solution, examining various inhibitor concentrations (10(-3) to 10(-6) M) and temperature ranges (303 to 333 K). Gravimetric measurements and electrochemical procedures were enhanced using atomic force microscopy (AFM), scanning electron microscopy (SEM), contact angle measurement (CA), and UV-visible spectroscopy. The protective effect on carbon steel increased with BTFI concentration but diminished with increasing temperature, achieving 98.6% at 1 mM below 303 K. Various thermodynamic and kinetic indices were computed and analysed. The adsorption of BTFI on the carbon steel surface adhered to the Langmuir adsorption isotherm. Potentiodynamic polarisation studies indicated that BTFI functioned as a mixed-type inhibitor. Surface studies showed that an adsorption-bound preventive layer of BTFI had formed on the carbon steel surface. Furthermore, AFM, SEM/EDX and CA results clearly show that BTFI can be efficiently adsorbed at the carbon interface and significantly reduce the corrosion of carbon steel. Additionally, theoretical investigations utilising Density Functional Theory (DFT) and Molecular Dynamics (MD) can clarify the reactive sites of the molecule and improve understanding of the adsorption process, complementing the experimental findings.