Nonplanar Monomer Strategy for Soluble Covalent Organic Frameworks with Reversible Thermal Behavior
Xinyu Yang1, Yingdi Zou2, Ningning He2,3
1Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu 610041, China.
ACS Applied Materials & Interfaces
|July 17, 2026
Summary
We developed a novel soluble covalent organic framework (COF) with heat-triggered solubility. This material enables efficient solution processing for applications like iodine sequestration membranes.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Conventional covalent organic frameworks (COFs) suffer from poor solubility and processability, hindering their practical applications.
- Developing soluble COFs is crucial for advancing materials science and enabling new functionalities.
Purpose of the Study:
- To design and synthesize a novel covalent organic framework (COF) with reversible heat-triggered solubility.
- To demonstrate the solution processability of the new COF for fabricating membranes and aerogels.
- To evaluate the COF membrane's performance in iodine sequestration from various media.
Main Methods:
- Synthesized a soluble heat-triggered solubility COF (HTS-COF) using a nonplanar monomer with a sterically congested, double-layered conjugated benzene ring.
- Characterized the HTS-COF's structure, solubility, and thermal responsiveness.
- Fabricated uniform membranes and aerogels from the HTS-COF via solution processing.
- Tested the HTS-COF membrane's efficiency and stability for iodine sequestration using dynamic filtration.
Main Results:
- The HTS-COF exhibits reversible solubility triggered by heat, attributed to enlarged interlayer spacing and attenuated π-π stacking.
- The material maintains crystallinity and structural integrity despite its enhanced solubility.
- Uniform membranes and aerogels were successfully prepared through solution processing.
- The HTS-COF membrane demonstrated rapid and highly efficient iodine sequestration from aqueous and organic solutions with excellent rejection and cycling stability.
Conclusions:
- The developed molecular design paradigm successfully overcomes the solubility limitations of conventional COFs.
- The HTS-COF offers a promising platform for solution-processable materials with tunable properties.
- The HTS-COF membrane shows significant potential for efficient iodine capture applications.
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