Adaptive Structural Reconfiguration in Ether-Incorporated Covalent Organic Frameworks Enables Efficient Iodine
Yuxin Liang1, Tao Liu1, Ruoqian Zhang1
1School of Marine Sciences (State Key Laboratory of Marine Resources Utilization in South China Sea), Hainan University, Haikou, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 5, 2026
Summary
Flexible covalent organic frameworks (COFs) show promise for radioactive iodine capture. Tailoring their structure, particularly ether bond flexibility, significantly impacts iodine adsorption efficiency and capacity, offering a new design principle.
Area of Science:
- Materials Science
- Environmental Chemistry
- Nanotechnology
Background:
- Efficient radioactive iodine capture is crucial for safety.
- Flexible covalent organic frameworks (COFs) offer potential but their adsorption mechanisms are unclear.
- Understanding structural reconfiguration's impact on iodine adsorption is needed.
Purpose of the Study:
- To design and synthesize flexible COFs with varying structural properties.
- To investigate the relationship between COF flexibility and iodine adsorption.
- To establish design principles for high-performance iodine adsorbents.
Main Methods:
- Synthesis of two flexible, ether-embedded COFs (F-TEA, F-BEA) and one rigid, ether-free COF (R-TPA).
- Characterization of COF structures and properties.
- Evaluation of iodine adsorption capacity in both vapor and aqueous phases.
Main Results:
- F-TEA showed superior iodine vapor capture due to reduced steric hindrance and enhanced interactions.
- F-BEA exhibited high iodine adsorption capacity (7.25 g g⁻¹) in aqueous solution via adaptive framework swelling and multi-site charge transfer.
- The rigid R-TPA showed poor performance and framework collapse.
Conclusions:
- Conformational control of flexible linkages is a key design principle for iodine adsorbents.
- Ether bond flexibility in COFs can be tuned to optimize iodine capture.
- This work provides insights into designing advanced materials for radioactive iodine remediation.
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