Highly crystalline covalent organic frameworks from flexible building blocks
Liqian Xu1, San-Yuan Ding2, Junmin Liu3
1Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China. zhengqy@iccas.ac.cn.
Chemical Communications (Cambridge, England)
|March 9, 2016
Summary
Two novel 2D covalent organic frameworks were synthesized using flexible triazine building blocks. These highly crystalline materials exhibit large surface areas, demonstrating controllable framework formation.
Area of Science:
- Materials Science
- Organic Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are crystalline porous polymers with tunable properties.
- Developing scalable synthesis methods for high-quality COFs remains a challenge.
- 2D COFs offer unique structural and electronic properties for various applications.
Purpose of the Study:
- To synthesize novel 2D covalent organic frameworks (COFs) on a gram scale.
- To investigate the self-assembly mechanism of triaryloxy-triazine building blocks.
- To characterize the structural and surface properties of the synthesized COFs.
Main Methods:
- Gram-scale synthesis of two novel 2D COFs (TPT-COF-1 and TPT-COF-2).
- Utilized flexible 2,4,6-triaryloxy-1,3,5-triazine as building blocks.
- Characterization techniques including X-ray diffraction (XRD) and BET surface area analysis.
Main Results:
- Successful synthesis of TPT-COF-1 and TPT-COF-2 with high crystallinity.
- Achieved large surface areas for both novel 2D COFs.
- Demonstrated controllable formation of highly ordered frameworks attributed to the Piedfort unit self-assembly.
Conclusions:
- Gram-scale synthesis of novel 2D COFs is feasible using flexible triazine precursors.
- The self-assembly of the Piedfort unit is crucial for ordered framework formation.
- The synthesized COFs possess desirable properties for potential applications in areas like gas storage or catalysis.
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