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

[Display omitted] • Air diffusion cathode is fabricated with Black Pearls 2000a by rolling method. • The catalyst layer contain abundant surface C C=O groups. • Current efficiency of >90% achieved at current density of up to 151 mA cm−2. • The cathode exhibits good applicability at the pH range of 1–13. H 2 O 2 production through electrochemical 2-electron reduction of oxygen (O 2) 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 C O groups, the ADC exhibits H 2 O 2 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 H 2 O 2 yield of up to 119.4 mg cm-2h−1 while CE dropped to 62.3 %. In addition, efficient H 2 O 2 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 H 2 O 2 and electrochemical advanced oxidation processes at practical scales. [ABSTRACT FROM AUTHOR]