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Electrochemical Frequency Modulation is a well-known technique which is mostly used for corrosion studies. It is generally performed in potentiostatic mode and allows calculating the corrosion current as well as Tafel parameters by rearranging the Butler-Volmer equation.However, no practical and theoretical approach has been published so far for EFM measurements in galvanostatic mode. This technique could be especially interesting for electrochemical power systems where galvanostatic control is much more beneficial because of easier operation. In contrast, even small potential changes during potentiostatic control can lead to high currents if a system has a very low internal resistance. This can lead to irreversible damages and safety risks. This study presents galvanostatic EFM measurements with fuel cells.

Carbon steel waste containers have been proposed in a number of national nuclear waste management programs. Although redox conditions in the sedimentary clay environments in which these containers would be placed will be anoxic, gamma irradiation would produce oxidizing conditions at the container surface. The effect of gamma radiation on carbon steel corrosion in de-aerated solutions was studied as a function of pH and temperature. The corrosion kinetics were studied by monitoring the corrosion potential (Ecorr) in-situ, and periodically performing linear polarization and electrochemical impedance spectroscopy measurements to determine polarization resistances. The surfaces, and cross sections of irradiated carbon steel coupon samples were also examined using SEM, XPS, and Raman spectroscopy. Preliminary results indicate that gamma irradiation increases the corrosion potential from a region where the anodic oxidation is limited to Fe(OH)2 and Fe3O4 to a region where the oxidation of Fe(OH)2 to gamma-FeOOH and Fe3O4 to gamma-Fe2O3 is possible.

An electrochemical quartz crystal microbalance (EQCM) has been used to examine the role of polyethylene glycol (PEG) and bis (sodiumsulfopropyl) disulfide (SPS) in the deposition of copper from acidified aqueous sulfate solutions containing chloride ions. Neither PEG nor SPS was observed to adsorb on copper at cathodic potentials in the absence of copper ions in solution. When a small amount of copper (principally Cu (II)) was introduced into solution by a double potential step, the adsorption of PEG was observed, as was the inhibition of that adsorption by SPS.