Boron Doped Diamond Electrodes: The Effect of Surface Pretreatment on Voltammetric Signals of Phenolic Compounds
Abstrakt
Electrooxidation of phenolic compounds causes severe fouling of electrode surface due to the formation of polymeric structures. In this contribution the effect of electrode pretreatment on the voltammetric signals of m-cresol and benzophenone-3 was studied at boron-doped diamond electrode.
The mechanical polishing by alumina and in-situ anodic activation at +2.4 V vs. Ag|AgCl, 3 mol.l-1 KCl) leads to well-developed voltammetric peaks in Britton-Robinson buffer pH 12.0 and 2.0, with the potential shift for m-cresol of ca 150 mV for the acidic and 450 mV for the base media to the more positive values for the latter activation method.
Obviously, the alumina-polished surface exhibits faster electron transfer kinetics for tested phenolic compounds, as for the redox couple [Fe(CN)6]3-/4-. For electroanalysis both approaches result in repeatable voltammetric signals and limits of detection in the 10-7 mol.l-1 concentration range.