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Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
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Covalent Organic Frameworks Containing Dual O2 Reduction Centers for Overall Photosynthetic Hydrogen Peroxide
Dan Chen1, Weiben Chen1, Yuting Wu2
1Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Science, Tianjin University, Tianjin, 300072, China.
Angewandte Chemie (International Ed. in English)
|December 28, 2022
Summary
New crystalline s-heptazine-based covalent organic frameworks (COFs) efficiently produce hydrogen peroxide (H2O2) via photocatalysis. These advanced COFs demonstrate enhanced solar-to-chemical efficiency, surpassing previous designs.
Area of Science:
- Materials Science
- Photocatalysis
- Green Chemistry
Background:
- Covalent organic frameworks (COFs) are promising for photocatalytic applications.
- Efficient production of hydrogen peroxide (H2O2) via overall photosynthesis is crucial for sustainable chemistry.
- Designing COFs with precisely controlled structures for enhanced H2O2 synthesis remains a significant challenge.
Purpose of the Study:
- To develop novel crystalline s-heptazine-based COFs for efficient photocatalytic H2O2 production.
- To investigate the structure-activity relationship of COFs with separated redox centers for overall photosynthesis.
- To enhance solar-to-chemical energy conversion efficiency in H2O2 synthesis.
Main Methods:
- Synthesis of crystalline s-heptazine-based COFs (HEP-TAPT-COF and HEP-TAPB-COF).
- Characterization of COF structures and redox properties.
- Photocatalytic evaluation of H2O2 production from O2 and water under visible light irradiation.
- Measurement of solar-to-chemical efficiency and apparent quantum efficiency.
Main Results:
- Successfully synthesized HEP-TAPT-COF and HEP-TAPB-COF with spatially separated redox centers.
- HEP-TAPT-COF demonstrated superior H2O2 production efficiency due to integrated dual O2 reduction sites.
- Achieved a remarkable solar-to-chemical efficiency of 0.65% and apparent quantum efficiency of 15.35% at 420 nm.
Conclusions:
- Spatially ordered active sites in HEP-COFs effectively promote charge separation for enhanced photocatalysis.
- HEP-TAPT-COF represents a significant advancement in COF-based photocatalysts for H2O2 production.
- The developed COFs offer a promising pathway for efficient and sustainable H2O2 synthesis.
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