Ionic liquids as green and sustainable steel corrosion inhibitors: Recent developments

Corrosion is a steel deterioration caused by chemical or electrochemical reactions with the environment. At present there exist various methods of the steel corrosion prevention, among which the most effective one is the use of corrosion inhibitors. Owing to the strict environmental restrictions – Registration, Evaluation, Authorization and Restriction of Chemicals (REACH), the development of green steel corrosion inhibitors is highly desirable. During the last few decades, the corrosion protection using ionic liquids attracts extensive attention of both the academy and industry. This article gives a brief outline of recent (2018–2021) achievements on ionic liquids as steel corrosion inhibitors. The influence of the ionic liquid composition (i.e. alkyl tail length, the presence of polar and non-polar substituents in cation and anion) as well as its concentration, and also temperature and nature of the medium on the steel anti-corrosion performance was discussed.