Three-Dimensional Covalent Organic Frameworks: From Topology Design to Applications
Bo Gui1, Guiqing Lin1, Huimin Ding1
1Sauvage Center for Molecular Sciences and Key Laboratory of Biomedical Polymers (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Accounts of Chemical Research
|September 8, 2020
Summary
Researchers developed a new strategy to synthesize three-dimensional covalent organic frameworks (3D COFs) using [4+4] condensation reactions. This breakthrough expands building block options and enables the creation of novel 3D COF structures with diverse applications.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are crystalline porous polymers with applications in various fields.
- Three-dimensional (3D) COFs offer large surface areas, hierarchical nanopores, and open sites, but their synthesis and structural determination remain challenging.
- Existing synthesis strategies for 3D COFs are limited to specific condensation reactions and building blocks, restricting functionalization and application diversity.
Purpose of the Study:
- To overcome limitations in 3D COF synthesis by developing a novel topology design strategy.
- To explore structure determination methods for polycrystalline 3D COFs.
- To expand the range of building blocks and demonstrate functionalization and applications of 3D COFs.
Main Methods:
- Developed a [4+4] condensation reaction strategy using tetrahedral and quadrilateral building blocks.
- Employed 3D electron diffraction techniques for structure determination of polycrystalline 3D COFs.
- Synthesized and functionalized diverse 3D COFs with characteristic properties.
Main Results:
- Successfully synthesized 3D COFs with a new 'pts' topology.
- Established a general synthetic strategy for creating 3D COFs with expanded building block options.
- Demonstrated the feasibility of atomic-resolution structure determination for polycrystalline 3D COFs.
- Showcased functionalized 3D COFs with potential applications.
Conclusions:
- The novel [4+4] condensation strategy significantly expands topology design options for 3D COFs.
- The developed methods facilitate structure determination and enable the creation of diverse, functionalized 3D COFs.
- This work provides a new paradigm for 3D COF research, opening avenues for future innovations in materials design and applications.
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