Heteroatom-Based Compounds as Sustainable Corrosion Inhibitors: An Overview

Heteroatoms (such as phosphorous, sulphur, oxygen and nitrogen) containing organic molecules exhibit remarkable efficiency towards corrosion inhibition. Their efficiency is attributed to the presence of lone pair of electrons and pi electrons in the molecule, due to which they are easily deposited on the metal surface. However, the organic compounds containing less electronegative heteroatoms generally show higher inhibition efficiency (IE) due to the facile migration of lone pair of electrons. Acidic solutions are widely used as electrolyte medium. The value of ∆G (Gibbs adsorption energy) reveals the nature of the inhibitors adsorb to the metal surface. Gravimetric and electrochemical analyses are extensively applied for the determination of corrosion inhibition. Similarly, surface analysis and theoretical investigation are also applied for supportive evidences. The purpose of the present review is to highlight the heteroatom-based potential corrosion inhibitors.