3D Covalent Organic Frameworks from Twistable Building Block Toward an Unprecedented ibd-r Topology for Efficient
Xilin Li1, Tongyi Zhao1, Yali Sun1
1Department of Chemistry, State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, 2699 Qianjin Street, Changchun, 130012, China.
Angewandte Chemie (International Ed. in English)
|December 16, 2025
Summary
Researchers developed novel three-dimensional covalent organic frameworks (3D COFs) with unique self-catenated structures. These advanced materials demonstrate exceptional performance in separating propylene from ethylene, achieving polymer-grade purity.
Area of Science:
- Materials Science
- Chemical Engineering
- Nanotechnology
Background:
- Designing three-dimensional covalent organic frameworks (3D COFs) with diverse structures for gas separation is challenging due to limited topological diversity.
- Existing 3D COFs often lack the specific pore features required for efficient separation of small molecules.
Purpose of the Study:
- To present a series of isoreticular 3D COFs synthesized using a [6+4] design strategy.
- To explore the impact of twistable building blocks on network topology and pore characteristics.
- To evaluate the gas separation performance of the synthesized 3D COFs, particularly for C3H6/C2H4 mixtures.
Main Methods:
- Synthesis of isoreticular 3D COFs (JUC-320, -321, -322) using a 6-coordinated building block and rectangular linkers.
- Utilizing a [6+4] design strategy with a twistable D3-symmetric building block.
- Employing dynamic breakthrough experiments to assess separation efficiency.
Main Results:
- Successful synthesis of JUC-320, -321, and -322 with an unprecedented self-catenated ibd-r topology.
- Achieved reduced pore sizes due to the torsional flexibility of the building blocks.
- Demonstrated exceptional C3H6/C2H4 separation performance with high adsorption ratios and selectivities.
- Obtained polymer-grade C2H4 (>99.99%) from mixtures via dynamic breakthrough experiments.
Conclusions:
- The [6+4] design strategy with twistable building blocks is effective for creating novel 3D COFs with unique topologies.
- The synthesized 3D COFs show significant promise for efficient C3H6/C2H4 separation.
- This approach offers a valuable method for constructing advanced 3D COFs for gas separation applications.
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