Kinetic data reporting the rate of electron transfer across an electrified interface are of fundamental as well as practical importance. They report the electric current caused by coupling the flow of electrons inside the electronically conducting electrode and the flow of ions in the adjacent ionically conducting phase. At equilibrium or rest, potential currents in both directions at the established dynamic equilibrium have the same absolute value: the net current is zero. This current describes the electrocatalytic activity of an electrode and is called the exchange current; with respect to the surface area, it is called the exchange current density. This study inspected the actually used surface areas because the reported activities may depend critically on the selection of this area. Charge transfer resistances corresponding to exchange currents I₀ were determined for a simple redox system using a platinum disc electrode with constant geometric surface area but variable roughness. At all studied degrees of roughness, changes in I₀ were found. With an electrochemically active surface area, exchange current densities j₀ could be calculated, but the obtained values showed a dependency on roughness that could not be accounted for by using this surface area instead of the geometric one. It is suggested that j₀ may be reported with respect to geometric surface area, but at least roughness data of the studied electrode should be provided.

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.

Graphene, graphene oxide, reduced graphene oxide, and few-layer graphene as functional coating materials for corrosion protection in devices for electrochemical energy conversion and storage are reviewed. Reported applications are briefly described, enabling the reader to make an informed decision about the protective options based on the reported achievements.

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.

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 their protective action, further details like substituents, heteroatoms and molecular geometry contribute. An overview is provided focused on aromatic inhibitors aiming at the identification of particularly promising inhibitors and their mode of action. Directions of further research and development are pointed out in conclusion.