The electrosynthesis of hydrogen peroxide (H2O2) via a two-electron oxygen reduction reaction enables decentralized H2O2 production. While metal-free carbon catalysts are sustainable and low-cost, their performance is hindered by poorly defined active sites and uncontrolled defect states. Here, we resolve these challenges through active site design and catalyst screening using fluorine (F) and nitrogen (N) codoped carbons as model materials. Statistical analysis combined with density functional theoretical calculations reveals that F-induced structural modification and defect passivation optimize OOH* binding, with F-doping and adjacent F atoms predominantly lowering abs ΔG(OOH*). Experimental results confirm that semi-ionic C–F bonds passivate defects in nitrogen-doped carbon, enhancing catalytic activity and durability. The resulting (N, F)-codoped carbon achieves nearly 100% H2O2 selectivity at 0.5–0.65 V versus the reversible hydrogen electrode and maintains > 95% across 0.01–0.65 V versus the reversible hydrogen electrode. In an electrolyzer, (N, F)-codoped carbon exhibits an H2O2 yield rate of 74.35 mol gcat.−1 h-1 and sustains 300 mA cm-2 for 105 hours with ~95% faradaic efficiency. Coupling the two-electron oxygen reduction reaction with methanol oxidation further reduces cell voltage and enhances productivity. This work provides a means to design efficient catalysts for industrial H2O2 electrosynthesis. The design of metal-free carbon catalysts is limited by unclear active sites and defects. Here, the authors combine statistical analysis with theoretical calculations to identify effective sites, guiding the synthesis of nitrogen and fluorine co-doped carbons for efficient hydrogen peroxide production.
Yu et al. (Wed,) studied this question.