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Updated: May 21, 2026
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Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
Published on: July 10, 2017
Acylhydrazone-Linked Covalent Organic Frameworks
Haipei Shao1,2, Xingyao Ye1, Yongzhi Chen1
1Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
Journal of the American Chemical Society
|May 20, 2026
Summary
This study introduces acylhydrazone-linked covalent organic frameworks (COFs) synthesized using ketones. These novel COFs exhibit enhanced stability, tunable light emission, and improved water adsorption properties.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are crystalline porous materials with tunable structures.
- Aldehydes are commonly used monomers for COF synthesis, but ketones remain underexplored.
- Acylhydrazone linkages offer potential for novel COF architectures and properties.
Purpose of the Study:
- To explore ketones as monomers for synthesizing COFs via acylhydrazone linkages.
- To investigate the impact of reaction conditions on COF crystallinity and porosity.
- To elucidate the role of acylhydrazone linkages in COF structure and function.
Main Methods:
- Solvothermal synthesis of COFs using ketones and hydrazides.
- Screening of reaction parameters (solvent, catalyst, temperature, time).
- Characterization of COF structure, porosity, and properties.
Main Results:
- Highly crystalline and porous acylhydrazone-linked COFs were successfully synthesized.
- Acylhydrazone linkages enhanced pore confinement, water adsorption, and adsorption heat.
- The COFs exhibited improved thermal/chemical stability, π-delocalization, tunable light emission, reduced bandgaps, and enhanced photoconductivity.
Conclusions:
- Ketones can be effectively utilized as monomers for COF synthesis, expanding the scope of COF design.
- Acylhydrazone linkages significantly influence COF structural and functional characteristics.
- This work presents a new strategy for developing advanced COFs with tailored properties for diverse applications.
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