An overview of anti-corrosion properties of ionic liquids for corrosion of carbon steel in acidic media

Abstract The review article summarizes various ionic liquids (ILs) used as corrosion inhibitors reported in the literature during the preceding five years (2016–2020) for corrosion of carbon steel in acidic solutions. The ILs are a green and sustainable choice for corrosion inhibition as compared to natural extracts as corrosion inhibitors due to lack of stability which restricts their application at the industrial level. The review discusses the inhibition efficiency of the ILs as corrosion inhibitors; the evaluation techniques like weight-loss method, potentiodynamic polarization, electrochemical impedance spectroscopy, etc., used for determination of inhibition efficiency and plausible mechanism of inhibition, adsorption isotherms are discussed. The review affirms that ionic liquids serve as excellent green corrosion inhibitors for carbon steel dissolution in acidic media. Most of the reported inhibition efficiency values ranged between 80 to 90% at minute concentrations which is valuable. The scope for further improvements is given for the benefit of readers.