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Updated: Jun 13, 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
Molecularly Precise Triangular Termination of Kagome Covalent Organic Framework Crystals Enabled by Side-Chain
Tianhao Xue1, Markus Döblinger1, Ignacio Munoz-Alonso1
1Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität (LMU), Munich, Germany.
Angewandte Chemie (International Ed. in English)
|June 11, 2026
Summary
Side-chain length controls ordering in 2D kagome covalent organic frameworks (COFs). The methoxy-substituted COF (OMe COF) shows superior crystallinity, enabling high-resolution TEM visualization of kagome lattices and surface functional groups.
Area of Science:
- Materials Science
- Nanotechnology
- Organic Chemistry
Background:
- High-resolution structural characterization of 2D kagome COFs is limited.
- Lattice ordering and surface functionality remain poorly understood.
- Need for precise structural insights to guide material design.
Purpose of the Study:
- To design and synthesize novel 2D kagome COFs with systematically varied side chains.
- To investigate the impact of side-chain length on framework crystallinity and ordering.
- To achieve high-resolution structural characterization of 2D kagome COFs using HRTEM.
Main Methods:
- Synthesis of acceptor-donor-acceptor linear linkers with varied alkoxy side chains.
- Imine condensation with a dibenzo[g,p]chrysene node to form 2D kagome COFs.
- High-resolution transmission electron microscopy (HRTEM) for structural analysis.
Main Results:
- Diverse 2D kagome COFs with methoxy, ethoxy, and propoxy side chains were synthesized.
- Side-chain length critically influenced framework crystallinity and ordering.
- The methoxy-substituted COF (OMe COF) exhibited superior crystallinity and large pores.
- HRTEM visualized extended kagome pore lattices and triangular terminations in OMe COF.
- Real-space evidence of exposed amino groups at crystal facets was obtained.
Conclusions:
- Side-chain engineering is crucial for controlling the crystallinity and ordering of 2D kagome COFs.
- High-resolution TEM can reveal detailed structural features, including pore terminations and surface functionality.
- These findings provide a structural foundation for designing functionalized 2D kagome COFs and interfacial engineering.
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