Polymorphism in Covalent Organic Frameworks Regulates Excited Dynamics for H2O2 Photosynthesis Coupled With Biomass
Yu-Ou He1, Wen-Yi Zheng1, Meng-Na Yue1
1Key Laboratory of Synthetic and Biological Colloids, School of Chemical and Material Engineering, Ministry of Education, Jiangnan University, Wuxi, P.R. China.
Angewandte Chemie (International Ed. in English)
|July 27, 2026
Summary
Polymorphism in covalent organic frameworks (COFs) impacts excited-state dynamics. This study engineered 1D and 2D COF polymorphs, revealing 1D-COFs enhance photocatalysis by suppressing energy loss.
Area of Science:
- Materials Science
- Photocatalysis
- Chemical Engineering
Background:
- Polymorphism in covalent organic frameworks (COFs) is key for structure-property relationships.
- The effect of COF polymorphism on excited-state dynamics is largely unexplored.
- Understanding these dynamics is crucial for designing efficient photocatalysts.
Purpose of the Study:
- To investigate the impact of framework architecture on excited-state dynamics and photocatalytic performance.
- To correlate topological differences in COF polymorphs with their efficiency in H2O2 photosynthesis and furfuryl alcohol valorization.
- To establish polymorphism engineering as a strategy for optimizing COF photocatalysts.
Main Methods:
- Synthesis of two chemically identical but topologically distinct 1D and 2D COF polymorphs (1D-TBPP-COF and 2D-TBPP-COF).
- Photocatalytic experiments for H2O2 generation and furfuryl alcohol oxidation.
- Mechanistic studies involving analysis of excited-state dynamics and charge-transfer processes.
Main Results:
- The 1D-TBPP-COF exhibited significantly higher H2O2 generation (18.75 mmol g-1 h-1) and furfuryl alcohol conversion to 6-hydroxy-2H-pyran-3(6H)-one (PN) (28.14 mmol·g-1·h-1) compared to the 2D counterpart.
- 1D-COFs suppressed vibrational relaxation losses and prolonged charge-transfer state lifetime due to steric constraints on aromatic ring rotation.
- 2D-COFs showed greater conformational flexibility, leading to non-radiative energy dissipation and lower photocatalytic efficiency.
Conclusions:
- Framework architecture in COF polymorphs critically influences excited-state dynamics and photocatalytic performance.
- Polymorphism engineering offers a viable strategy to control excited-state properties and enhance photocatalytic activity.
- This study provides fundamental insights into manipulating COF structures for advanced photocatalytic applications.
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