Graphene-modified electrode. Determination of hydrogen peroxide at high concentrations.

A gold electrode partially coated by graphene multilayer is developed and tested with respect to high concentrations of hydrogen peroxide. The effective use of conventional
electrode materials for the determination of such an analyte by
anodic oxidation or cathodic reduction is prevented by the
occurrence of adsorptions fouling the electrode surface. This
prevents reliable and repeatable voltammetric curves for being
recorded and serious problems arise in quantitative analysis via
amperometry. The gold–graphene electrode is shown to be
effective in quantitative evaluation, by cathodic reduction, of
hydrogen peroxide at concentration levels that are of interest in
an industrial. Acid, neutral, and basic pH values have been
tested through correct adjustment of a Britton Robinson buffer.
The experiment s have been performed both by cyclic voltammetry and with amperometry at constant potential in unstirred solution. The latter technique has been employed in drawing a calibration linear plot. In particular, the performances of the developed electrode system have been compared with
those of both pure gold and pure graphene electrode
materials. The bi-component electrode was more sensitive; co-catalytic action by the combination of the two
components is hypothesised. The system is stable over many potential cycles, as checked by surface-enhanced Raman spectra recorded over time.