Ethanol oxidation current-potential relations

In particular, the electrooxidation of ethanol over Pt in acidic media has two major hmitations which prevent its viability as it was discussed by Koper [109]. The first relates to the fact that reaction predominantly produces acetate and acetic acid intermediates thus resulting in only 2 and 4 electrons respectively which are only very minor contributions to the possible current. Both are thus unwanted side products for fuel cell applications. The second limitation is that the path to CO2 is rather difficult in that it requires the activation of C-C bond as well as the oxidation of both the CHx and CO intermediates that form. Both of these intermediates tend to inhibit or poison metal surfaces at lower potentials [110]. 

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