Boosting Hydrostability and Carbon Dioxide Capture of Boroxine‐Linked Covalent Organic Frameworks by One‐Pot Oligoamine Modification

• Published in: Chemistry : a European journal Vol. 29; no. 29; pp. e202300186 - n/a
• Main Authors: Jia, Chao, Liang, Rong‐Ran, Gan, Shi‐Xian, Jiang, Shu‐Yan, Qi, Qiao‐Yan, Zhao, Xin
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 22.05.2023
• Subjects: Boron; Carbon dioxide; carbon dioxide capture; Carbon sequestration; Chemistry; COF-1; covalent organic frameworks; Flue gas; hydrostability; Low pressure; oligoamine; oligoamine; carbon dioxide capture; covalent organic frameworks; COF-1; hydrostability
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202300186

Boron‐based covalent organic frameworks (COFs) are susceptible to nucleophilic attack by water at the electron‐deficient boron sites and even slightly humid air could destroy the integrity of their porous frameworks within hours. Such instability is a major limitation to the practical applications of boron‐based COFs. Herein we report a significant enhancement of hydrostability of boroxine‐linked COFs (COF‐1 as representative) by modification with an oligoamine (tetraethylenepentamine, TEPA), which leads to survival of the modified COF in water and long‐time stability under humid atmosphere. Meanwhile, the TEPA modification also results in a considerable increase in CO2 adsorption capacity up to 13 times and a dramatic improvement in CO2/N2 selectivity in low pressure region, which make the modified COF suitable for capturing CO2 from flue gas. This work provides a facile, efficient, and scalable method to greatly improve hydrostability of boroxine‐linked COFs and reshape them into high‐performance CO2 adsorbents. Killing two birds with one stone. The representative of boroxine‐linked COFs, COF‐1, is modified with an oligoamine by one‐pot condensation. The modification with the oligoamine not only boosts the water stability of COF‐1, but also significantly increases its CO2 uptake capacity and CO2/N2 selectivity, especially in low pressure region. These advantages make the oligoamine‐modified COF‐1 suitable for capturing CO2 from humid flue gas.