A concise review on corrosion inhibitors: types, mechanisms and electrochemical evaluation studies

This article presents a concise review of different types of inhibitors for corrosion protection on metal surfaces. Corrosion inhibitors can be of different types, which include organic, inorganic and hybrid (organic/inorganic) materials. They are also classified as cathodic, anodic and/or mixed-type inhibitors, which are based on the active inhibitor molecules that retard the corrosion process. Silicate, nitrites, molybdates, phosphates, zinc salt and cerium salt are widely used as inorganic inhibitors. Many organic compounds have been widely utilized as inhibitors. Corrosion protection will be obtained by various mechanisms such as physisorption, chemisorption, barrier protection, thin-film formation and electrochemical processes. The type of inhibitors, inhibition mechanism and the evaluation methods have been explained in detail.