Sauerstoffüberspannung in gegenwart verschiedener ionen in abhängigkeit von der aktivität des wassers

T. Erdey-Grúz, É Szetey, G. Horányi

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The changes of the overpotential of oxygen evolution caused by the change of concentration or activity of water and by the presence of alkali metal ions were investigated in aqueous HClO4, H2SO4 and H3PO4 solutions at Pt electrodes. The water content of the solutions was changed by dissolved ε{lunate}-caprolactam. It was established that the overpotential of electrochemical oxygen evolution at constant current density increases with decreasing water activity and the relation between overpotential and activity of water is rather different in the three acids investigated. The current-voltage curves correspond to the Tafel equation partially with two sections of differing slope. The effect of concentration of alkali metal ions on the overpotential was studied as a function of the water activity. The sequence of the overvoltage increasing effect of the different metal ions is dependent on the activity of the water and on the concentration of the ions. The results indicate that the change of the liquid structure of the water caused by the presence of the different ions and ε{lunate}-caprolactam can exert an influence on the velocity of oxygen evolution.

Original languageGerman
Pages (from-to)177-191
Number of pages15
JournalJournal of Electroanalytical Chemistry
Issue number1
Publication statusPublished - Oct 25 1975

ASJC Scopus subject areas

  • Analytical Chemistry
  • Chemical Engineering(all)
  • Electrochemistry

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