High‐Current‐Density H 2 O 2 Synthesis Toward Paired Electrolytic Upgrading of Ethylene Glycol

ABSTRACT The high‐efficiency electrosynthesis of hydrogen peroxide (H 2 O 2 ) via two‐electron oxygen reduction reaction (2e − ORR) represents a promising alternative to the traditional anthraquinone process. However, achieving high selectivity, industrial‐grade stability, and on‐site utilization of H 2 O 2 remains a significant challenge. Here, we designed a single‐atom catalyst, CoNPC, featuring a Co–N/P co‐coordination structure, tailored for high‐current‐density H 2 O 2 electrosynthesis and relevant paired valorization of ethylene glycol. The P modulation optimized the electronic structure of Co centers, leading to enhanced selectivity (> 90%) and stable H 2 O 2 production for over 140 h at a high current density of −200 mA cm −2 . In situ spectroscopic studies and theoretical calculations revealed that the P heteroatom plays a critical role in optimizing *OOH binding energy, thereby facilitating the 2e − ORR process. The electrogenerated H 2 O 2 was further utilized in a Fenton‐like process to oxidize ethylene glycol to formic acid. By coupling this cathodic reaction with anodic EG electrooxidation, we demonstrated a paired electrolysis system that enables simultaneous value‐added products at both sides. This work not only offers a robust strategy for the design of single‐atom catalysts on industrial H 2 O 2 electrosynthesis but also pioneers an energy‐efficient paired electrolysis system for waste utilization.