Diverse crystal size effects in covalent organic frameworks.
Tianqiong Ma1,2, Lei Wei3, Lin Liang2
1College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences (BNLMS), Peking University, 100871, Beijing, P.R. China.
Nature Communications
|December 1, 2020
Summary
This study reveals crystal size effects in covalent organic frameworks (COFs). Crystal size impacts pore integrity in LZU-111 and structural flexibility in COF-300, influencing material properties and applications.
Area of Science:
- Materials Science
- Chemistry
Background:
- Crystal size significantly influences material properties and functions.
- Crystal size effects in covalent organic frameworks (COFs) remain largely unexplored due to synthesis challenges.
Purpose of the Study:
- To investigate the impact of crystal size on the properties of two representative COFs.
- To establish a structure-property correlation at micro- and mesoscales for COFs.
Main Methods:
- Successfully synthesized COFs with controlled crystal sizes.
- Analyzed the influence of crystal size on pore surface area, pore integrity, structural flexibility, and sorption selectivity.
Main Results:
- For LZU-111 (rigid spiral channels), crystal size affects pore surface area by altering pore integrity.
- For COF-300 (flexible straight channels), crystal size influences structural flexibility and sorption selectivity by changing the number of repeating units.
Conclusions:
- Demonstrated diverse crystal size effects in COFs, dependent on their structural characteristics.
- Provided insights into structure-property relationships at multiple scales, advancing COF applications.
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