In this study, the cathodic reduction of oxygen was thought to be dominant and the effect of the anodic reaction
at the scratch was presumably small.
Hence, for study of the corrosion mechanism of pure aluminum in alkaline solution, it is enough to consider indirect metal dissolution by consecutive film formation and dissolution as a partial anodic reaction
The metabolically produced sulfide was oxidized directly at electrode, providing an anodic reaction
that produces sulfate or thiosulfate.
(positive electrode), Oxidation of Water
If the mass transfer of species is not a limiting factor, the corrosion rate is determined using mixed potential theory and the Butler-Volmer equation under the condition of the rate of anodic reaction
being equal to the rate of cathodic reaction:
A strongly spontaneous or prevalent cathodic reaction can push a sluggish anode towards corrosion or a very sluggish cathodic reaction can be used to hinder a very spontaneous anodic reaction
Corrosion, in what is known as an anodic reaction
, involves the movement of metal from a surface into a solution as an electrically charged species.
At the graphite anode, the main anodic reaction
in the electrophoretic cell is the decomposition reaction of water to produce [H.
In MMCs reinforced with conducting materials, the presence of less conductive phase at the interface is quoted  as not providing an easier path for electron exchange for oxygen reduction and driving the anodic reaction
at a higher rate.
This is the preferred anodic reaction
(2) since it eliminates the potential for an increased corrosion rate from the generation of oxygen.
The anodic reaction
is balanced by the cathodic reaction, which is catalyzed by oxidized metals and does not occur to significant degree in the absence of a solid metal.
4), (16) So, it can be concluded that PAni coatings on active metals like iron provide anodic protection, act as electronic, chemical, and physical barriers to inhibit anodic reaction
, and maintain high resistance to ionic flow--thereby blocking the metal dissolution and providing excellent corrosion protection.