Related Experiment Video
Updated: May 25, 2026
08:42
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
Single Crystals of Perylene Diimide-Based Two-Dimensional Covalent Organic Frameworks
Ling Zhang1,2, Zixuan Chen3, Lukas Mühlnickel4
1Faculty of Chemistry and Food Chemistry, TUD Dresden University of Technology, Dresden, Germany.
Advanced Materials (Deerfield Beach, Fla.)
|May 23, 2026
Summary
Researchers developed a new method to synthesize single crystals of two-dimensional covalent organic frameworks (2D COFs). This breakthrough enables detailed studies of their electronic properties and structure-photophysical relationships.
Area of Science:
- Materials Science
- Organic Chemistry
- Crystallography
Background:
- Two-dimensional covalent organic frameworks (2D COFs) are advanced porous polymers with tunable properties.
- Synthesizing single crystals of 2D COFs is challenging but crucial for fundamental research and applications.
- Existing methods have yielded limited examples of 2D COF single crystals.
Purpose of the Study:
- To develop a novel synthetic strategy for growing high-quality single crystals of 2D COFs.
- To explore the synthesis of perylene diimide (PDI)-based 2D COFs using the new method.
- To investigate the photophysical properties of these single-crystal 2D COFs.
Main Methods:
- A high-temperature double-modulator synthetic strategy was employed.
- Single crystals were grown from fully dissolved precursors.
- Perylene diimide (PDI)-based 2D COFs were synthesized and characterized.
- Micro-spectroscopy and polarization-dependent photoluminescence (PL) measurements were performed.
Main Results:
- The new method successfully produced single crystals of PDI-based 2D COFs, with lateral dimensions up to 50 µm.
- Photoluminescence measurements showed both ultrafast monomer-like and slower excimer-related emission.
- Polarization-dependent measurements revealed linear polarization of the fast PL component, indicating parallel chromophore orientation.
Conclusions:
- The developed synthetic strategy is effective for producing large single crystals of 2D COFs.
- 2D COF single crystals are invaluable for detailed structure-photophysical property investigations.
- This work advances the understanding and potential applications of covalent organic frameworks.
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