Topology-Selective Manipulation of Two-Dimensional Covalent Organic Frameworks
Xinyu Wang1,2, Minghui Liu1,2, Youxing Liu3
1Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China.
Journal of the American Chemical Society
|November 27, 2023
Summary
Researchers synthesized two distinct 2D covalent organic frameworks (COFs) by changing acid catalysts, creating unique structures with varied properties for diverse applications. This advances 2D COF topology and structure-property understanding.
Area of Science:
- Materials Science
- Chemistry
Background:
- Manipulating topological architectures in 2D covalent organic frameworks (COFs) is crucial for tailored applications but presents significant challenges.
- Developing methods for topology-selective synthesis of 2D COFs is an active area of research.
Purpose of the Study:
- To report the topology-selective synthesis of two distinct 2D COFs: imine-based HT-COFs and benzimidazole-fused BI-HT-COFs.
- To investigate how altering acid catalysts influences the resulting COF topology and properties.
Main Methods:
- Utilized Schiff base reactions and imine-based cyclization reactions.
- Employed different acid catalysts to direct the synthesis towards specific topological structures.
- Characterized the synthesized COFs to understand their structural, electronic, and chemical properties.
Main Results:
- Successfully synthesized two distinct 2D COFs with different topologies: HT-COFs with a triangular channel superlattice and BI-HT-COFs with a hexagonal lattice.
- Observed marked differences in bandgap, chemical stability, molecular adsorption, and catalytic activity between the two COFs.
- Demonstrated that simple changes in acid catalysts lead to significant variations in COF structure and properties.
Conclusions:
- The study diversifies the known topologies of hexaaminotriphenylene-based 2D COFs.
- Highlights clear structure-property relationships, facilitating fundamental research and potential applications of 2D COFs.
- Provides a facile method for controlling 2D COF topology through catalyst selection.
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