The stabilising influence of hematin on the properties of the oxygen-sensitive carbon electrode

Carbon films obtained by the spray-pyrolysis technique were applied to the construction of electrodes sensitive to dissolved oxygen. Four types of the carbon electrodes were examined: virgin carbon from polyfurfuryl alcohol ( A), virgin carbon with a hematin film (B), Fe-modified carbon (C), and Fe-m odified carbon covered with a film of hematin (D). The layer of hematin bas ically played the role of an accumulator of physically adsorbed oxygen. The application of the hematin film yielded carbon electrodes of better stabil ity. Such an electrode exhibited the capability for the very strict two ele ctron reduction of oxygen molecule in the relatively wide range of oxygen c oncentration in water. Except for electrochemical tests, all types of carbo n electrodes (including the hematin covered one) were examined using XP spe ctroscopy, FT-IR spectroscopy, and SE microscopy. (C) 1999 Elsevier Science S.A. All rights reserved.