Three-Dimensional Fully Conjugated Covalent Organic Frameworks from a Hexaconnected sp2-Carbon Building Unit.
Jie Zhang1, Chuanbao Jiao1, Haorui Zheng1
1State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Changchun 130012, P. R. China.
Journal of the American Chemical Society
|April 29, 2026
Summary
Researchers developed novel 3D covalent organic frameworks (COFs) using a unique 6-connected building block. These materials exhibit excellent charge transport and photocatalysis, paving the way for advanced organic electronics and catalysis.
Area of Science:
- Materials Science
- Organic Chemistry
- Nanotechnology
Background:
- Two-dimensional conjugated materials have advanced organic electronics and photocatalysis.
- Synthesizing three-dimensional (3D) conjugated materials is challenging due to a lack of high-connectivity building blocks.
Purpose of the Study:
- To design and synthesize a novel 6-connected, all sp2-hybridized carbon building block.
- To construct 3D covalent organic frameworks (COFs) using this new building block.
- To investigate the electronic and photocatalytic properties of the resulting 3D COFs.
Main Methods:
- Synthesis of cyclododecahexaene-hexathiophene-hexaaldehyde (CDHTh-6CHO), a 6-connected conjugated building block.
- Incorporation of CDHTh-6CHO into 3D COFs (JUC-690, -691, -692).
- Characterization of charge transport properties (Hall electron mobility) and photocatalytic activity (thioanisole oxidation).
Main Results:
- Successfully synthesized unprecedented 3D COFs from a high-connectivity conjugated core.
- Achieved band-like charge transport with tunable Hall electron mobilities up to 1.32 cm2 V-1 s-1.
- Demonstrated excellent photocatalytic performance in selective aerobic oxidation of thioanisole (up to 99% yield).
Conclusions:
- Introduced a pioneering architecture for high-connectivity conjugated building blocks.
- Established a new platform of 3D fully conjugated COFs with significant potential.
- Highlighted the promise of these materials for optoelectronics and heterogeneous photocatalysis.
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