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Electrosynthesis of hydrogen peroxide by partial reduction of oxygen in alkaline media. Part II: Wall-jet ring disc electrode for electroreduction of dissolved oxygen on graphite and glassy carbon

Department of Physical Chemistry, Babeş-Bolyai University, Klausenburg, Cluj, Romania
Journal of Applied Electrochemistry (Impact Factor: 2.41). 02/2000; 30(2):187-192. DOI: 10.1023/A:1003830813424

ABSTRACT

A wall-jet ring disc electrode was constructed by adapting a wall-jet flow through electrochemical cell. Commercially available spectral graphite and glassy carbon were used as working disc electrodes and the ring electrode was made of stainless steel. The efficiency and rate constants, measured in a planar parallel flow hydrodynamic regime, indicated the partial electroreduction of dissolved oxygen as a quasi-reversible two-electron process for both electrode materials tested.

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    • "The method consisted to measure the limiting current (I lim ) when the potential of the working electrode (a spectral graphite disc electrode; 3 mm diameter) was fixed at À0.2 V versus Ag/AgCl/1 M KCl reference electrode. For a flowtrough electrochemical cell the I lim value depends on the flow conditions as well as on the experimental set-up characteristics, i.e. the flow rate (V f ), the distance between the working electrode and the inlet-nozzle (d), the length and the diameter of the tubing, the size of the sample and dilution loops etc. [10] [11] [12] [13]. Given that the investigated cell was one of a wall-jet type, V f and d play a major role in establishing the hydrodynamic regime at the electrode surface. "
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