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

The inhibition capacity of carbon steel (CS) in 0.5M H2SO4 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 (eta %) 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.

Automated summary

The study found that 8-hydroxyquinoline grafted triazole derivatives have good inhibition performance towards carbon steel in sulfuric acid medium, with inhibition efficiency increasing with concentration, in line with the Langmuir adsorption isotherm model.