Mb/ddab electrodes catalytically reduce solutions of nitrite (as indicated by the large increase of current) at two distinct potentials, labeled A and B.  This is indicative of seperate reductive reaction steps.  By following each wave's behavior, we can identify and characterize the individual steps.

The different waves, or steps, have very different pH dependence. The potential of Wave A changes dramatically with pH, while the current at Wave B decreases dramatically with increasing pH. This indicates that wave B is a multiproton, multielectron process.

Electrolysis with inline mass spectroscopy

To look for gaseous products, i.e. like those of denitrification, we used inline electrolysis / mass spectroscopy of the headgas over a bulk electrolysis.  Because of interference from CO₂ and N₂ in the air, we used ¹⁵N-labeled nitrite.

See a picture of an inline electrolysis cell on Mekki's homepage!

... By following the species formed at different potentials, we can correlate the gas production with the electrochemical mechanism.

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