Electrogeneration of hydrogen peroxide by oxygen reduction using anodized graphite felt

Abstract

BackgroundElectrocatalytic synthesis of H2O2 by oxygen reduction is regarded as the most promising alternative to AO process, and thus, design of a cost-effective and highly active cathode of vital significance. MethodsThis work modified graphite felts via anodic oxidation process in NH4HCO3 aqueous, and demonstrated the electrogeneration of H2O2 by using modified graphite felt cathode. The surface properties of different modified graphite felt were investigated. Various conditions of the process, including potential, reaction pH, and O2 flux, were optimized. Significant findingsThrough the modification, the beneficial functional groups COO and C=O has considerable increased, which lead the kinetics of ORR enhanced and H2O2 electrochemical production increased. The maximum accumulation rate of H2O2 achieved 2.00 mg/h/cm2 at the conditions of -0.60 V (vs.SCE), 0.4 L/min oxygen flow rate and pH 3. The modified cathode kept a stable performance for H2O2 electrochemical synthesis during 5 cycles.