The Synergistic Effect of NaHSO4 and NaCl Salts on Corrosion Inhibition Performance of Two Gemini Cationic Surfactant Ionic Liquids

Abstract

In this study, two imidazolium-based ionic liquid surfactants (TSIL and EFAIL) were first synthesized, and then investigated the synergistic effects of NaHSO4 and NaCl salts on corrosion inhibition performance of TSIL and EFAIL inhibitors on low carbon steel samples in 1 M HCl solution. For this aim, the electrochemical techniques of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), surface morphology analyses, and quantum chemical calculations were employed. Results showed that adding salts to acidic solutions containing EFAIL and TSIL increased their inhibition efficiency. Furthermore, addition of NaHSO4 to TSIL-containing solution could further increase the inhibition efficiency compared to other mixtures of the salts and the inhibitors. The DFT results also revealed that the energy gap of TSIL is lower than that of EFAIL, implying that TSIL has more chemical reactivity and less kinetic stability than EFAIL.