Roza Kenzhegalieva, Meruyet Khapiyeva, Gauhar Uzakbay, Aruzhan Talapova, Ruben Vardanyan and Nikolay Akatyev            

The present study investigates the inhibitory properties of sodium anthraquinone-2-sulfo-nate  (AQ2SNa).  Weight  loss  measurements,  electrochemical  tests,  and  metal  surface analysis were carried out in this study to evaluate the adsorption behavior of the compound and its influence on the corrosion rate of carbon steel in 0.5 mol dm-3H2SO4solution. Density functional theory DFT/B3LYP/6-311+G(d,p) and molecular  dynamic simulation  (MD) were applied  for  theoretical  studies  to  evaluate  the  inhibiting  effect  and  understand  the mechanism of interaction of inhibitor molecules with Fe (110) surface. Itwas found that the inhibition efficiency of AQ2SNa in 0.5 mol dm-3 H2SO4solution reached up to 94.44 % at the maximum concentration (0.5 g dm-3). Thermodynamic parameters show that the adsorp-tion  process  is  spontaneous  and endothermic,  suggesting  the  conformance  of  strong interactions  between  inhibitor  and  metal  surface  according  to the Langmuir  adsorption model. The spontaneous physisorption (ΔG0ads˃ -20 kJ mol-1) of the inhibitor molecules led to high efficiency. Analysis of dynamic polarization curves showed that AQ2SNa acts as an inhibitor of a mixed nature. The results also indicate that AQ2SNa significantly increases the contact angle, indicating increased hydrophobicity due to the formation of a stable film on the metal surface. Theoretical parameters were compared to experimental data. The results highlight  the  novel  potential  of  AQ2SNa  as  an  effective  corrosion  inhibitor  to  provide  an effective solution for enhancing the protection of carbon steel in acidic media.

Reference to the article: Kenzhegalieva, R., Khapiyeva, M., Uzakbay, G., Talapova, A., Vardanyan, R., & Akatyev, N. (2025). A new potential of sodium anthraquinone-2-sulfonate as a corrosion inhibitor for carbon steel in 0.5 M H2SO4. Journal of Electrochemical Science and Engineering, 15(2). https://pub.iapchem.org/ojs/index.php/JESE/article/view/2512/2392