From Discrete Molecular Cages to a Network of Cages Exhibiting Enhanced CO2 Adsorption Capacity

• Published in: Angewandte Chemie International Edition Vol. 56; no. 27; pp. 7787 - 7791
• Main Authors: Zhang, Lei, Xiang, Long, Hang, Cheng, Liu, Wenlong, Huang, Wei, Pan, Yichang
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 26.06.2017; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Adsorption; cage compounds; Cages; Carbon dioxide; carbon dioxide storage; Carbon sequestration; Chemistry; Chemistry, Multidisciplinary; Enthalpy; hierarchically porous materials; Physical Sciences; Porosity; Porous materials; Schiff bases; Science & Technology; sodium; Sorption; Voids; Schiff bases; carbon dioxide storage; SORPTION; COVALENT ORGANIC FRAMEWORKS; sodium; hierarchically porous materials; MICROPOROSITY; ISOTHERMS; ACTIVATED CARBONS; CHEMISTRY; NANOTUBES; cage compounds; CRYSTALLINE; CARBON-DIOXIDE
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.201702399

We have adopted the concept of “cage to frameworks” to successfully produce a Na–N connected coordination networked cage Na‐NC1 by using a [3+6] porous imine‐linked organic cage NC1 (Nanjing Cage 1) as the precursor. It is found that Na‐NC1 exhibits hierarchical porosity (inherent permanent voids and interconnected channel) and gas sorption measurements reveal a significantly enhanced CO2 uptake (1093 cm3 g−1 at 23 bar and 273 K) than that of NC1 (162 cm3 g−1 under the same conditions). In addition, Na‐NC1 exhibits very low CO2 adsorption enthalpy making it a good candidate for porous materials with both high CO2 storage and low adsorption enthalpy. Networking: Hierarchically porous structures are prepared by linking discrete shape‐persistent porous organic cages with sodium ions. The resulting cage network has an excellent CO2 storage capacity along with low adsorption enthalpy compared to the discrete cage precursor.