Abstract
Electrocatalytic ethaneperoxoic acid (EPA) reduction at gold electrode in 0.5 M H2SO4 by ferric ions has been studied. Ferric ions acted as a mediator for EPA reduction where EPA is reduced via EC mechanism. The voltammetric behaviour of EPA has not been affected with the coexisting H2O2 or oxygen in naturally aerated EPA solutions. It has been found that ferric ions mediate EPA reduction but not H2O2. Interestingly while the EPA reduction peak is obtained at gold electrode in Fe3+ free H2SO4 is at around 0.2 V vs. Ag/AgCl, it is obtained at around 500 mV in the presence of ferric ions, i.e., it is around 300 mV positively shifted. The difference between the peak potential for EPA and H2O2 at gold electrode equals 0.5 and 0.9 V in the absence and presence of ferric ions, respectively. The large difference in the peak potentials in the presence of ferric ions, in addition to the well-defined reduction peak of EPA, has been utilized as a base for a selective analysis of EPA in the presence of H2O2 with acceptable sensitivity.