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Updated: Jul 23, 2025
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
8.2K
Symmetry-breaking dynamics in a tautomeric 3D covalent organic framework
Yangyang Xu1, Tu Sun1,2, Tengwu Zeng1
1School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
Nature Communications
|July 14, 2023
Summary
Researchers stabilized and switched tautomeric states in a dynamic 3D covalent organic framework (COF). This breakthrough enables control over photoelectronic properties and visual sensing applications.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Enolimine-ketoenamine tautomerism is used for 2D covalent organic frameworks (COFs), offering chemical robustness and photoelectronic activity.
- Controlling tautomeric states and their structure-property relationships in COFs remains challenging due to proton transfer equilibrium.
Purpose of the Study:
- To stabilize and switch tautomeric states in a dynamic 3D COF (dynaCOF-301).
- To correlate tautomeric structure with photoelectronic properties.
- To explore applications in sensing.
Main Methods:
- Constructed a dynamic 3D COF (dynaCOF-301) using hydroquinone and a tetrahedral building block via imine linkages.
- Utilized symmetry-asymmetry tautomerization (diiminol to iminol/cis-ketoenamine).
- Investigated host-guest interactions and guest molecule removal/inclusion to control tautomeric states and framework dynamics.
Main Results:
- Achieved stabilization and switching of tautomeric states in dynaCOF-301 through structural transformation and guest interactions.
- Demonstrated reversible framework deformation and ordering-disordering transitions between solvated, activated, and hydrated phases.
- Observed solvatochromic and hydrochromic effects indicating potential for visual sensing.
Conclusions:
- Dynamic 3D COFs can be designed to control tautomeric states and their associated photoelectronic properties.
- dynaCOF-301 exhibits responsive behavior to guest molecules, enabling tunable properties.
- The observed chromic effects suggest utility in naked-eye chemosensing applications.
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