Electrochemical, XPS and theoretical examination on the corrosion inhibition efficacy of stainless steel via novel imidazolium ionic liquids in acidic solution

Three novel ionic liquids (3-(2-ethoxymethyl)-1-octyl-1H-imidazol-3-ium chloride, 1-decyl-3-(2-ethoxymethyl)-1H-imidazol-3-ium chloride and 1-dodecyl-3-(2-ethoxymethyl)-1H-imidazol-3-ium chloride) were manufactured and their chemical structures were confirmed by spectra tools (FT-IR, 1H NMR, and 13C NMR). The inhibition impact of the new ionic liquids on stainless steel (201 SS) in 2.0 M HCl solution was examined via various electrochemical measurements. These measurements revealed that the new ionic liquids are excellent inhibitors even at very low concentrations. The findings confirmed that the new ionic liquids inhibit both cathodic and anodic processes while also improving corrosion resistance. The polarization curves confirmed that the ionic liquids produced function as mixed inhibitors. This attitude is determined by the cation type and concentration of ionic liquids. The anti-corrosion properties of ionic liquids are based on their adsorption potential. The relation between molecular structure and its inhibitive action has been explored and discussed by DFT & Monte Carlo Simulation methods. Furthermore, the XPS was carried out with and without the synthesized ionic liquids on the 201 SS samples. There is a strong approach between the collected data from electrochemical, surface, and theoretical studies.