Molecular inhibitors added to the corrosive medium attacking metallic materials are a well-established way of combating corrosion. The inhibitive action proceeds via adsorption of the inhibitor on the surface to be protected. Aromatic building blocks in the inhibitor play a major role in its protective action, and further details like substituents, heteroatoms, and molecular geometry contribute. An overview focused on aromatic inhibitors is provided, aiming at the identification of particularly promising inhibitors and their mode of action. Directions for further research and development are pointed out in the conclusion.

A reference electrode is a half-cell (an electrode) with a stable, well-defined and highly reproducible electrode potential. A vast number of electrodes have been developed for different applications. They are briefly presented. For the common types, the advantages and drawbacks are discussed. Practical hints for daily use are provided.

Molecular aromatic corrosion inhibitors are frequently applied to slow down the corrosion of iron, its alloys and numerous other metallic materials. This case study with three representative aromatic inhibitors and a pure iron electrode aims at the verification of the reported conclusions regarding these inhibitors and at the verification and comparison of electrochemical corrosion assessment methods with attention to differences between iron alloys (steels) and pure iron possibly related to the presence/absence of alloying elements and non-iron impurities.