The structure of layered covalent-organic frameworks
Binit Lukose1, Agnieszka Kuc, Thomas Heine
1Center for Functional Nanomaterials, School of Engineering and Science, Jacobs University Bremen, Research III, Room 61, Campus Ring 1, 28759 Bremen, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 25, 2011
Summary
The stacking arrangement of 2D Covalent-Organic Frameworks (COFs) is re-evaluated. New models show serrated or inclined stacking is more stable, increasing surface area and pore surface polarization.
Area of Science:
- Materials Science
- Chemistry
Background:
- Covalent-Organic Frameworks (COFs) are porous crystalline materials composed of light elements.
- Previously, 2D COFs were assumed to have an AA stacking arrangement, except for COF-1 (AB stacking).
Purpose of the Study:
- To investigate and propose a more accurate stacking arrangement for 2D COFs.
- To reconcile experimental data with theoretical models for COF structures.
Main Methods:
- Computational modeling and analysis of existing experimental data, including powder X-ray diffraction (XRD) patterns.
- Evaluation of structural stability for different stacking configurations.
Main Results:
- The study demonstrates that COF-1, COF-5, COF-6, and COF-8 exhibit greater stability with serrated or inclined stacking arrangements.
- A layer shift of approximately 1.4 Å compared to perfect AA stacking is proposed.
- These revised structures align with experimental observations and XRD data.
Conclusions:
- The commonly accepted AA stacking for 2D COFs is revised.
- The proposed serrated/inclined stacking models enhance material stability.
- These findings lead to increased surface area and pore surface polarization in COFs.
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