Membrane-free Electrolysis Production of Hydrogen Peroxide on Low-cost Metal-free Electrocatalysts for Dye Degradation

Abstract

The efficient production of hydrogen peroxide (H2O2) solution was achieved by combining cathodic two-electron oxygen reduction (2e− ORR) and anodic two-electron water oxidation (2e− WOR) in two half-reaction cells. h-BN loaded on carbon fibers (h-BN@C) is prepared and employed as an anode material to catalyze 2e− WOR, while sulfonated commercial BP-2000 carbons (BP-2000-SO3H) were prepared as the cathode materials for 2e− ORR. In a 2 M KHCO3 solution, an overall Faradaic efficiency of 97 % and a total H2O2 production rate of 1872 mmol g−1 h−1 over metal-free electrodes were accomplished in a membrane-free flow cell. The dilute H2O2 solution could be directly used to degrade Rhodamine B, methyl blue and methylene orange dyes in water. This work proved low-cost production of dilute H2O2 solution in simple membrane-free flow cells with single electrolyte and on-site utilization for efficient dye degradation.