Tandem Photocatalytic H₂O₂ Production and In Situ Upgrading Enabled by Docking and Locking Engineered Covalent...

Area of Science:

• Materials Science
• Catalysis
• Organic Chemistry

Background:

• Photocatalytic hydrogen peroxide (H2O2) generation faces challenges with low yields and difficult purification.
• These limitations hinder the widespread practical application of H2O2 in synthesis.

Purpose of the Study:

• To develop an integrated tandem catalytic strategy for simultaneous H2O2 generation and in situ utilization.
• To engineer covalent organic frameworks (COFs) as platforms for efficient tandem photoredox catalysis.

Main Methods:

• Designed and synthesized a TTPh-OH COF using a "docking and locking" strategy.
• Evaluated H2O2 production rates in pure water and isopropanol/water mixtures.
• Demonstrated the in situ consumption of photogenerated H2O2 for organic synthesis (hydrobromination).

Main Results:

• Achieved benchmark H2O2 production rates of 11.42 mmol g⁻¹ h⁻¹ (water) and 61.96 mmol g⁻¹ h⁻¹ (isopropanol/water).
• Generated 22.1 mM H2O2 using a single-photocatalyst tandem platform.
• Successfully drove the hydrobromination of 4-methylstyrene with 99% conversion and 87% selectivity.

Conclusions:

• The developed tandem catalytic system efficiently produces and utilizes H2O2, overcoming previous limitations.
• This approach offers a blueprint for sustainable, solar-driven photoredox catalysis for value-added organic synthesis.
• Demonstrated the practical viability of in situ generated H2O2 in organic transformations.