A Visible Light Responsive Smart Covalent Organic Framework with a Bridged Azobenzene Backbone
Liang Qiang1, Hao Bai1, Xin-Yi Li1
1Chongqing Key Laboratory of Soft-Matter Material Chemistry and Function Manufacturing, The Key Laboratory of Applied Chemistry of Chongqing Municipality, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, P. R. China.
Macromolecular Rapid Communications
|December 22, 2023
Summary
Researchers created a novel porous material, COF-bAzo-TFPB, that responds to light. This covalent organic framework exhibits reversible photoisomerization, enabling applications in controlled release and UV-sensitive functions.
Area of Science:
- Materials Science
- Organic Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are crystalline porous polymers with tunable properties.
- Developing stimuli-responsive COFs is crucial for advanced applications.
- Azobenzene-containing materials offer photo-responsive capabilities.
Purpose of the Study:
- To synthesize a novel visible light-responsive 2D covalent organic framework.
- To investigate the photoisomerization behavior of the azobenzene unit within the framework.
- To explore potential applications in photo-controlled processes.
Main Methods:
- Condensation reaction between 3,3'-diamino-2,2'-ethylene-bridged azobenzene and 1,2,4,5-tetrakis-(4-formylphenyl) benzene.
- Characterization of the resulting porous material (COF-bAzo-TFPB) for its structure, surface area, crystallinity, and stability.
- Investigation of the photoisomerization of the incorporated azo units under visible light irradiation.
Main Results:
- Successful synthesis of COF-bAzo-TFPB, a 2D porous covalent organic framework.
- The material exhibits a large surface area, good crystallinity, and notable thermal and chemical stability.
- The azo units within the COF-bAzo-TFPB skeleton demonstrate reversible photoisomerization upon visible light exposure.
Conclusions:
- The designed linker enables photo-responsive behavior in the COF-bAzo-TFPB.
- This work expands the utility of covalent organic frameworks for photo-controlled release, guest molecule uptake, and dynamic photoswitching.
- The developed material shows promise for UV-sensitive applications.
Keywords:
3,3′-diamino-2,2′-ethylene-bridged azobenzenecarbon dioxide capturecovalent organic frameworksreversible photoswitchingMore Related Videos
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