Covalent organic frameworks constructed from flexible building blocks: high porosity, crystallinity, and iodine uptake

Abstract

Two covalent organic frameworks (F-COF-1 and F-COF-2) synthesized from flexible building units have been designed and constructed through Schiff base condensation reactions under solvothermal conditions. Interestingly, two F-COFs displayed good...

Construction of a conjugated covalent organic framework for iodine capture

“…Due to their high surface area, low density and regular pore structure, COFs are suitable as a solid-phase adsorbent and have been studied as adsorbent materials for iodine capture. [10][11][12][13][14][15][16][17][18][19][20][21] For example, Fang et al synthesized tetrathiafulvalene-based COFs and achieved excellent iodine adsorption capacity through the synergistic effect of physical and chemical adsorption. 16 Recently we have also reported a pyrene-based two-dimensional COF (TFPPy-TMPD-COF) with a vapor capacity of 4.8 g g −1 due to the combination of chemisorption and physisorption, 19 in which the introduction of 2,3,5,6-tetramethyl-p-phenylenediamine (TMPD) was helpful for changing the pore environment to enhance the iodine adsorption capacity of the COF.…”

Enhancing the Iodine Adsorption Capacity of Pyrene‐Based Covalent Organic Frameworks by Regulating the Pore Environment

“…[8] As a typical class of porous and crystalline organic materials, utilization of COFs as adsorbent materials for iodine capture has attracted much attention due to their well-defined structure, low density, high surface area, and regular pore structure. [9][10][11][12][13][14][15][16][17][18][19][20][21] For examples, Jiang et al constructed several COFs with different channel shapes for iodine sorption, and found that the pore volume was key to the uptake capacity; [9] Zeng et al synthesized a serial of TJNU-COFs with very high iodine adsorption capacities based on a twisted three-connected unit (1,3,5-trimethyl-2,4,6-tris(4-aminophenyl)benzene), in which the incorporation of twisted units in frameworks contributed to efficiently expose the chemisorption site for increasing the sorption capacity. [14,15] From these examples, it can been drawn out that COFs are an ideal platform for iodine capture and pore structure modification can efficiently increase iodine sorption capacity.…”

Evaluation of an Imine-Linked Polymer Organic Framework for Storage and Release of H2S and NO

“…Because of its versatility, this reaction is widely used. It involves the reaction of amines (e.g., 1,3,5-triazine-2,4,6-triamine (melamine), 1,4-bis-(2,4-diamino-1,3,5-triazine)-benzene,1,2,4,5-benzenetetramine, 2,3,6,7,10,11-hexaaminotriphenylene,2,3,6,7,14,15-hexaaminotriptycene, and 2,4,6-triaminopyrimidine) with aldehyde or ketone compounds (e.g., terephthalaldehyde, isophthalaldehyde, thieno[2,3-b]thiophene-2,5-dicarboxaldehyde, 1,3,5-benzenetricarboxaldehyde, and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde) without expensive catalysts [ 8 , 16 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. The obtained porous network materials may be crystalline (crystalline covalent organic frameworks (COFs)) or amorphous (imine-linked polymer organic frameworks (i-POFs)).…”