Hydrogen peroxide (H₂O₂) is a key green oxidant extensively used in chemical synthesis, wastewater treatment and medical disinfection. Electrosynthesis of H₂O₂ through the two-electron oxygen reduction reaction (2e⁻ ORR) features distinct merits including mild reaction conditions and environmental friendliness, rendering it a promising alternative to the traditional anthraquinone process. Currently, developing electrocatalysts with high activity, high selectivity, and robust durability, as well as realizing synergistic optimization of electrodes, electrolytic devices, and operational parameters, constitute critical bottlenecks restricting the large-scale deployment of this technology. Accordingly, this review comprehensively summarizes recent progress on H₂O₂ electrosynthesis via the 2e⁻ ORR. We first elaborate fundamental reaction mechanisms and catalyst design strategies. Afterwards, the modulation effects of integrated device systems on catalytic activity, selectivity, and stability are analyzed from the aspects of electrode structure, reactor configuration, and key operational parameters. Finally, the challenges and prospective opportunities facing H₂O₂ electrosynthesis systems are proposed, offering insights to facilitate the further development of this emerging field.

The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling. Herein, in this work, CuO/Co₃O₄ with heterogeneous interface is successfully constructed as a bifunctional catalyst for the electrooxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid and the electroreduction of nitrate to ammonia (NH₃). The open-circuit potential spontaneous experiment shows that more 5-hydroxymethylfurfural molecules are adsorbed in the Helmholtz layer of the CuO/Co₃O₄ composite, which certifies that the CuO/Co₃O₄ heterostructure is conducive to the kinetic adsorption of 5-hydroxymethylfurfural. In situ electrochemical impedance spectroscopy further shows that CuO/Co₃O₄ has faster reaction kinetics and lower reaction potential in oxygen evolution reaction and 5-hydroxymethylfurfural electrocatalytic oxidation. Moreover, CuO/Co₃O₄ also has a good reduction effect on NO₃^-. The ex-situ Raman spectroscopy shows that under the reduction potential, the metal oxide is reduced, and the generated Cu₂O can be used as a new active site for the reaction to promote the electrocatalytic conversion of NO₃^- to NH₃ synthesis. This work provides valuable guidance for the synthesis of value-added chemicals by 5-hydroxymethylfurfural electrocatalytic oxidation coupled with NO₃^- while efficiently producing NH₃.