Industrial H2O2 Electrosynthesis in Neutral Saltwater Over Polythiophene-Modulated Edge-Nickel Sites in Conductive Metal-Organic-Framework

Electrochemical hydrogen peroxide (H 2 O 2 ) synthesis in neutral saltwater holds promise for medical sterilization and marine remediation, but is limited by the scarcity of catalysts combining high selectivity and industrial-current capability. Here, we report a polythiophene-modulated strategy to activate the edge-nickel sites in the conductive metal-organic framework (Ni-HHTP) for efficient H 2 O 2 electrosynthesis via two-electron oxygen reduction reaction (2e − ORR). The polythiophene with sufficient oxygen-containing species in situ coordinated with the edge Ni-sites in Ni-HHTP to form a penta-coordinated Ni-O 5 configuration, thus tailoring the electronic structure of nickel centers and optimizing the 2e − ORR activity and selectivity. Meanwhile, Ni-HHTP possesses a well-defined porous architecture, in which polythiophene is incorporated and significantly enhances its electronic conductivity, favoring rapid reaction kinetics. Thus, the resulting catalyst achieves over 90% H 2 O 2 selectivity in simulated seawater (3.6 wt.% NaCl), and operates stably at an industrial current density of 250 mA cm −2 . When integrated into a solar-driven system, there is still an average Faradaic efficiency of ∼100% for H 2 O 2 electrosynthesis, as well as a solar-to-H 2 O 2 conversion efficiency of 12.8%. This work demonstrates the precise activation of metal sites in conductive metal-organic frameworks via polymer modulation, offering a practical avenue for industrial-scale H 2 O 2 electrosynthesis under neutral conditions.