Dual-Knot and Dual-Linkage Design Strategy of 2D COFs: Toward Robust Proton-Conducting Platforms
Keiichiro Maegawa1, Hassan Alipour1, Vellaichamy Joseph1
1Next-Generation Energy Systems Group, Centre of Excellence ENSEMBLE3, Warsaw, Poland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|February 25, 2026
Summary
Researchers developed a novel dual-knot design for covalent organic frameworks (COFs), creating complex structures with enhanced properties. These new COFs show high proton conductivity and stability, paving the way for advanced energy materials.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are crystalline porous materials with significant application potential.
- Current COF designs are limited by single-knot and single-linker architectures, restricting complexity and tunability.
Purpose of the Study:
- To introduce a dual-knot, dual-linkage design strategy for 2D COFs.
- To synthesize and characterize novel COFs with enhanced structural complexity and functional properties.
Main Methods:
- Developed a dual-knot strategy combining C3-symmetric and C2 linkers with two distinct C3 knots.
- Synthesized two new COFs: imide-imine COF (II-COF) and imide-β-ketoenamine COF (IK-COF).
- Investigated the proton conductivity and cycling stability of PA-loaded COFs.
Main Results:
- Successfully synthesized unprecedented II-COF and IK-COF materials.
- The dual-knot architecture provides multiple heteroatom adsorption sites.
- PA-loaded COFs demonstrated high anhydrous proton conductivity and excellent cycling stability.
- Synergistic effects of pyridinic nitrogens, imine nitrogens, and carbonyl oxygens contribute to conductivity.
Conclusions:
- Established a generalizable strategy for creating compositionally complex and symmetry-defined COFs.
- Highlighted the potential of these novel COFs as robust platforms for proton conduction.
- The dual-knot design offers a pathway for developing advanced functional materials.
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