8-hydroxyquinoline grafted triazole derivatives as corrosion inhibitors for carbon steel in H2SO4 solution: Electrochemical and theoretical studies

Abstract

The inhibition capacity of carbon steel (CS) in 0.5M H 2 SO 4 by three 8-hydroxyquinoline grafted triazole derivatives (EHTC, AHTC, and MHTC) have been investigated using electrochemical impedance spectroscopy ( EIS ), potentiodynamic polarization ( PPD ), and weight loss measurements ( WLM ) at 298 K. Generally, the results clearly show that the inhibition performance (η %) increases with an increase in the concentration of EHTC, MHTC, and AHTC, reaching a maximum value of 95.5% (EHTC), 95.1% (MHTC), and 94.1% (AHTC) at the optimal concentration (10 −3 M) for PPD technical. The PPD shows that EHTC, AHTC, and MHTC behave as mixed-type inhibitors. In addition, the inhibitor obeys the single layer adsorption isotherm of Langmuir. Scanning electron microscopy ( SEM ) analysis of the CS has also been investigated and discussed. The theoretical calculations and MD simulations show a better correlation with the experimental results for the studied triazole derivatives.