Topological Control Over Porphyrin-Based Covalent Organic Frameworks for Elucidating Electron Transfer
Kai Xu1, Yaoqian Feng1, Fuxiang Wen1
1State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310058, China.
Angewandte Chemie (International Ed. in English)
|April 23, 2025
Summary
This study introduces new porphyrinic 2D COFs with diverse topologies, revealing how structural design impacts electron transport and electrocatalysis for energy applications.
Area of Science:
- Materials Science
- Chemistry
Background:
- Two-dimensional covalent organic frameworks (2D COFs) offer tunable properties but lack structural diversity, especially porphyrin-based COFs, limiting exploration.
- The prevalent sql topology in porphyrin COFs restricts structural variety and hinders comprehensive structure-property relationship studies.
Purpose of the Study:
- To design and synthesize porphyrinic 2D COFs with varied topological configurations (sql and bex).
- To investigate the impact of topological engineering on structural, electronic, and electrochemical properties.
- To develop advanced electrocatalysts for oxygen evolution reactions.
Main Methods:
- Systematic design and synthesis of porphyrinic 2D COFs with sql and bex topologies.
- Comprehensive structural characterization using advanced techniques.
- Electrochemical investigations and band structure analysis.
- Development and testing of nickel-incorporated bex-COFs for oxygen evolution.
Main Results:
- Precise control over lattice geometries achieved, yielding monoporous (sql) and biporous (bex) structures.
- Topology-governed electron transport observed, with bex topology showing enhanced electron transfer efficiency.
- Electronic structures modulated by topological configuration and chemical composition.
- Optimized Ni-BBFPP-TAPP-COF (bex topology) demonstrated superior oxygen evolution performance (342 mV at 10 mA cm⁻²).
Conclusions:
- Expanded structural diversity of porphyrinic 2D COFs beyond the sql topology.
- Established explicit correlations between topological engineering and electrocatalytic performance.
- Provided fundamental design principles for advanced energy conversion materials using topological control.
Keywords:
2D PolymersCovalent organic frameworksElectron transferOxygen evolution reactionTopological controlMore Related Videos
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