Efficient hydrogen peroxide production at high current density by air diffusion cathode based on pristine carbon black

H2O2 production through electrochemical 2-electron reduction of oxygen (O2) is a promising route whereas the faradaic efficiency is generally limited under high current density. In this work, a three-layer air diffusion cathode (ADC) is fabricated with carbon black (CB, black pearls 2000) and PTFE by rolling method. On account of the porous surface with dominant meso and micro pores, high hydrophobic and abundant surface CO groups, the ADC exhibits H2O2 yield of 85.2 ± 0.5 mg cm-2h−1, and current efficiency (CE) of 90.6 ± 0.4 % at 151 mA cm−2 during a 20-cycle operation. Further elevating the current density to 301 mA cm−2 results in H2O2 yield of up to 119.4 mg cm-2h−1 while CE dropped to 62.3 %. In addition, efficient H2O2 yields are achieved at wide pH range of 1.0–13.0. The applicability and stability of the ADC indicate its great potential for electrosynthesis of H2O2 and electrochemical advanced oxidation processes at practical scales.