Electrochemical synthesis of hydrogen peroxide on oxygen-fed graphite/PTFE electrodes modified by 2-ethylanthraquinone

This paper reports an investigation on the performance of a catalyzed H2O2 electrogeneration process using a modified oxygen-fed graphite/PTFE electrodes in which the redox catalyst was incorporated into the graphitic mass. The organic redox catalyst chosen for the modification was 2-ethylanthraquinone (EAQ). The H2O2 electrogeneration rate was optimized relative to potential and catalyst concentration. Hydrogen peroxide formation rate on oxygen-fed graphite/PTFE was greatly improved by the presence of the organic redox catalyst and the overpotential for oxygen reduction was shifted more positive. During electrolysis, hydrogen peroxide electrogeneration reaction showed a pseudo-zero-order kinetics and apparent rate constants increased with EAQ concentration. For the electrodes containing 10% of EAQ, apparent rate constants were 30% higher at a potential 400 mV more positive when compared to the performance of a non catalyzed electrode.