Solving the COF trilemma: towards crystalline, stable and functional covalent organic frameworks
Frederik Haase1, Bettina V Lotsch
1Institute of Functional Interfaces, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, Bldg. 330, 76344 Eggenstein-Leopoldshafen, Germany. frederik.haase@kit.edu.
Chemical Society Reviews
|November 6, 2020
Summary
Covalent organic frameworks (COFs) are advanced porous polymers. New strategies now enable the creation of crystalline and stable COFs, overcoming previous limitations for diverse applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are emerging porous polymers with tunable properties.
- Key features include crystallinity, diverse topologies, and accessible pores.
- Enhanced stability is a critical but underdeveloped aspect of COFs.
Purpose of the Study:
- To review rational approaches for engineering stability and crystallinity in COFs.
- To address the challenge of achieving simultaneously crystalline, stable, and functional COFs.
- To explore new avenues for real-world COF applications.
Main Methods:
- Discussing strategies that bypass the crystallinity-stability dichotomy.
- Examining methods like tweaking reaction conditions for reversible linkages.
- Highlighting approaches such as separating order and stability induction steps, and controlling structural degrees of freedom.
Main Results:
- Identification of three major strategies for obtaining stable and crystalline COFs.
- Demonstration that new methods can overcome the inherent challenges in COF design.
- Paving the way for enhanced COF performance and broader applicability.
Conclusions:
- Rational design approaches are crucial for advancing COF stability and crystallinity.
- Overcoming current challenges unlocks potential for novel COF applications.
- The field is maturing, moving towards practical implementation of advanced COFs.
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