Intramolecular Charge Transfer-Regulated Isomeric Covalent Organic Frameworks for Multiple Solvent-Response
Ke Shi1, Yaze Chen1, Haijiao Peng1
1Pingyuan Laboratory, College of Chemistry, Zhengzhou University, Zhengzhou, 450000, China.
Small (Weinheim an Der Bergstrasse, Germany)
|March 25, 2025
Summary
Two new isomeric covalent organic frameworks (COFs) show distinct color changes in response to multiple solvents. This breakthrough enables advanced applications in information encryption and anti-counterfeiting technologies.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Stimulus-responsive covalent organic frameworks (COFs) exhibit color changes upon exposure to external stimuli.
- Investigating multiple solvent-responsive COFs is challenging due to synthesis difficulties and uncontrollable charge transfer processes.
Purpose of the Study:
- To synthesize novel isomeric COFs with regulated intramolecular charge transfer (ICT) for distinct solvent responses.
- To explore the potential of these COFs in information encryption and anti-counterfeiting.
Main Methods:
- Synthesis of two novel isomeric COFs by modulating donor/acceptor distance and linkage.
- Characterization of solvatochromic behaviors in water, acid, and halogenated solvents.
- Analysis of ICT enhancement mechanisms via hydrogen bond, protonation, and halogen/π interactions.
Main Results:
- The synthesized isomeric COFs displayed significantly distinct solvatochromic behaviors.
- Multiple solvent responsiveness was attributed to varied ICT process enhancements through specific interactions.
- The COFs demonstrated excellent performance as stimulation-responsive materials for image and data encryption.
Conclusions:
- This work offers a new approach for designing multiple solvent-responsive COFs.
- The developed COFs show promising potential for advanced applications in information encryption and anti-counterfeiting.
Keywords:
information encryptionisomeric covalent organic frameworksmultiple solvent‐responsivesolvatochromic propertiesMore Related Videos
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