Metal-free oxygen-functionalized carbon materials are promising electrocatalysts for selective hydrogen peroxide (H 2 O 2 ) production via the two-electron oxygen reduction reaction (ORR). However, specifically controlling oxygen moieties while maintaining scalability remains challenging. Herein, we present a scalable and sustainable Friedel–Crafts reaction-assisted carbonization strategy that converts lignin into oxygen-tunable carbon catalysts for efficient H 2 O 2 electrosynthesis. Electrochemical measurements reveal a strong correlation between carbonization temperature, oxygen speciation, and catalytic performance. Specifically, carbonyl and carboxyl groups enhance H 2 O 2 selectivity, while hydroxyl groups suppress H 2 O 2 formation by preferentially binding O* intermediates. Density functional theory corroborates these findings, indicating that carbonyl and carboxyl groups favor the two-electron pathway. Accordingly, selective blocking of hydroxyl groups achieves >95% H 2 O 2 selectivity, a production rate of 575.5 mmol g cat -1 h -1 at 0.4 V RHE , and stable operation for 40 h. This renewable, low-cost platform couples mechanistic control with scalable synthesis, potentially enabling decentralized H 2 O 2 generation in on-site disinfection and wastewater treatment. • Scalable Friedel–Crafts strategy enables oxygen-tunable metal-free carbon catalysts. • Carbonyl and carboxyl promote the 2e - ORR pathway, while hydroxyl groups suppress selectivity. • Hydroxyl blocking yields >95% H 2 O 2 selectivity with high H 2 O 2 productivity. • Life-cycle analysis confirms low environmental impact for decentralized H 2 O 2 production.
Ahn et al. (Sun,) studied this question.