Organic inhibitors overpotential

The low overpotential regions with metal dissolution and inhibition. The results from these investigations include information concerning aspects of metal dissolution, mobility of surface atoms, and the blocking actions of both noble metal atoms and organic inhibitors. 

In acid conditions oxide films are not usually present on the metal surface and the cathodic reaction is primarily that of hydrogen discharge rather than oxygen reduction. Thus, inhibitors are required that will adsorb or bond directly onto the bare metal surfaces and/or raise the overpotential for hydrogen ion discharge. Inhibitors are usually organic compounds... 

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