Surface Electrochemistry of Uranium Dioxide in Acidic Hydrogen Peroxide Solutions
نویسندگان
چکیده
The electrochemical reduction of H2O2 on SIMFUEL was investigated over the pH range 1 to 4. The mechanism at pH 4 is known to occur on U species incorporated into a surface layer of U1-2xU2xO2+x. However, below pH 3, reduction occurs on an adsorbed UO2(OH) state which is unstable and oxidizes to insulating U before dissolving as UO2. Both schemes are observed at intermediate pH’s. The presence of both low and high acidic regions at the electrode surface is determined by the combination of peroxide concentration, bulk pH and the surface diffusion conditions.
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تاریخ انتشار 2012