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Updated: Aug 5, 2026
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Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Dynamic Coordination-Enabled Metal-Dependent Configurational Switching in a Covalent Organic Framework
Si Huang1, Hai-Sen Xu1, Liang Song1
1GBRCE for Functional Molecular Engineering, LIFM, IGCME, School of Chemistry, Sun Yat-Sen University, Guangzhou510275, China.
Journal of the American Chemical Society
|July 27, 2026
Summary
Researchers developed a new strategy using dynamic coordination to create reconfigurable covalent organic frameworks (COFs). These materials can change shape and properties based on metal ion coordination, enabling tunable functions like photocatalysis.
Area of Science:
- Materials Chemistry
- Supramolecular Chemistry
- Coordination Chemistry
Background:
- Synthesizing crystalline materials with controllable structural transformations is challenging.
- Covalent Organic Frameworks (COFs) offer tunable properties but often lack dynamic structural adaptability.
- Dynamic covalent chemistry and coordination chemistry are key areas for developing responsive materials.
Purpose of the Study:
- To develop a dynamic coordination-mediated strategy for constructing reconfigurable COFs.
- To investigate the metal-induced structural transformations and their impact on material properties.
- To explore the application of these adaptive COFs in photocatalysis.
Main Methods:
- Synthesis of a bis-acylhydrazone-linked COF (COF-LIFM20-Zn) with a dynamic Zn coordination center.
- Investigating reversible U-W configuration switching via demetalation/remetalation of Zn(II).
- Reprogramming the framework to a J-shaped configuration using Cu(II) coordination.
Main Results:
- Achieved reversible U-W switching with high Zn(II) removal (96.2%) and remetalation (97.9%) over three cycles.
- Demonstrated metal-induced interconversion among U-, W-, and J-shaped configurations within a single framework.
- Showcased metal-dependent modulation of pore structure and photophysical properties, including photocatalytic NAD+ regeneration.
Conclusions:
- Established a versatile strategy for reconfigurable COFs by integrating dynamic covalent and coordination chemistry.
- Demonstrated metal-induced control over framework structure, pore environment, and photocatalytic activity.
- Opened new avenues for designing adaptive crystalline materials with programmable functions.
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