Electron Transfer-Proton Supply Decoupling at Functionalized Polymer Interfaces Enables Efficient Air-Fed H₂O₂...

Area of Science:

• Electrochemistry
• Materials Science
• Sustainable Chemistry

Background:

• Electrochemical hydrogen peroxide (H₂O₂) production via the two-electron oxygen reduction reaction (2e⁻ ORR) is a sustainable alternative but faces limitations.
• Low O₂ availability and coupled electron-proton transfer hinder efficiency in air-fed systems.

Purpose of the Study:

• To develop a bifunctional covalent organic polymer interface for efficient H₂O₂ electrosynthesis directly from air.
• To decouple electron transfer from proton supply for stabilized 2e⁻ ORR under O₂-lean conditions.

Main Methods:

• Constructed a bifunctional covalent organic polymer interface (QSPIP-TMC@CB) on carbon black.
• Integrated carbonyl electron-relay units and quaternary ammonium cationic motifs.
• Investigated the mechanism of electron injection and proton regulation.

Main Results:

• Achieved a H₂O₂ production rate of 3410.1 mmol·h⁻¹·g⁻¹ with 91.4% Faradaic efficiency (FE<0xE2><0x82><0x95><0xE2><0x82><0x82><0xE2><0x82><0x82>) directly from air.
• Demonstrated stable operation at 100.0 mA·cm⁻² for 35.0 h.
• Enabled gram-scale H₂O₂ production (4.8 g h⁻¹) with high efficiency.

Conclusions:

• The functionalized interface effectively decouples electron and proton transfer, stabilizing the 2e⁻ ORR pathway.
• This strategy provides a general and scalable design paradigm for air-fed H₂O₂ electrosynthesis.
• The approach is extendable to other ORR catalysts, showcasing broad applicability.