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Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Published on: July 10, 2017

Cage Based Crystalline Covalent Organic Frameworks.

Jian-Xin Ma^1,2, Jian Li³, Yi-Fan Chen⁴

¹Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.

Journal of the American Chemical Society

|February 19, 2019

Summary

This summary is machine-generated.

Researchers developed novel cage-based crystalline covalent organic frameworks (COFs) with permanent porosity for CO2 adsorption. These unique structures bridge 2D and 3D COFs, merging porous organic cages with extended frameworks.

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Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

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Area of Science:

Materials Science
Supramolecular Chemistry
Nanotechnology

Background:

Covalent organic frameworks (COFs) are crystalline porous polymers with tunable structures.
Developing novel COF architectures is crucial for advanced material applications.
Bridging porous organic cages and extended frameworks offers new design possibilities.

Purpose of the Study:

To construct novel cage-based crystalline covalent organic frameworks (COFs).
To investigate the structural characteristics and porosity of the synthesized cage-COFs.
To evaluate the CO2 adsorption capabilities of these new materials.

Main Methods:

Synthesis of cage-COF-1 and cage-COF-2 using a prism-like molecular cage and diamine linkers.
Structural characterization using techniques like 13C CP/MAS NMR.
Porosity and gas adsorption measurements, focusing on CO2 uptake.

Main Results:

Successfully synthesized two new cage-based COFs (cage-COF-1 and cage-COF-2) with hexagonal skeletons.
The unique structure features pillared cage nodes and hanging linkers, creating trigonal channels and interconnected pores.
The cage-COFs exhibit permanent porosity and demonstrate effective CO2 adsorption facilitated by intrinsic cage cavities.

Conclusions:

The novel cage-COFs merge characteristics of 2D and 3D COFs, bridging porous organic cages and extended crystalline organic frameworks.
These materials possess permanent porosity and show potential for CO2 capture applications.
The study introduces a new class of COFs with unique structural and functional properties.