High iodine uptake in two-dimensional covalent organic frameworks

Abstract

Two two-dimensional covalent organic frameworks (COFs, TJNU-203 and TJNU-204) with high crystallinity and large specific surface areas are rationally fabricated from a three-connected distorted building block and linear linkers. The...

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

“…The flexible pores also may have had elasticity and self-adapting abilities for iodine capture. 24 The iodine uptake capacity of F-COF-2 was comparable to those of reported 2D-COFs such as SIOC-COF-7 (4.81 g g −1 ), 17 TPB-DMTP-COF (6.32 g g −1 ), 18 TJNU-203 (5.89 g g −1 ), 19 C-TP-BPDA-COF (6.11 g g −1 ), 20 a and TTA-FMTA-COF (5.07 g g −1 ). 20 b The ability of the F-COFs to retain adsorbed iodine was also investigated, as shown in Fig.…”

“…7–10 Essentially “perfect” levels of porosity and stability for skeletons of COFs have been achieved and used for diverse functions including gas adsorption and separation, luminescent sensors, and energy applications. 11–23…”

“…Zhao and co-authors reported two new COFs that showed good porosity and that showed high iodine uptake levels. 19 All of the above COFs use neutrally charged skeletons for iodine vapor uptake. Zhai and co-workers, in contrast, synthesized cationic COFs via a simple post-function method to give a state-of-the-art ability to capture iodine via electrostatic interactions.…”

Flexible three-dimensional diacetylene functionalized covalent organic frameworks for efficient iodine capture

“…To our best knowledge, the iodine capture capacities of both COFs are much higher than those of most reported porous materials. We summarize the iodine uptakes of typical adsorbents in Table S1;† for example, the capacity of the CPOF-3 is 21-fold higher than that of Ag-MOR (0.28 g g −1 ) and far superior to those of representative porous materials, 18 such as ZIF-8 (1.25 g g −1 ), 19 HKUST-1 (0.64 g g −1 ), 20 PAF-1 (1.86 g g −1 ), 21 PAF-24 (2.76 g g −1 ), 22 NiP-CMP (2.02 g g −1 ), 23 COF-DL229 (4.70 g g −1 ), 24 SIOC-COF-7 (4.81 g g −1 ), 25 COF-300 (3.50 g g −1 ), 26 TJNU-204 (5.34 g g −1 ), 27 TpPa-1 (2.45 g g −1 ), 28 and BTPOC (3.21 g g −1 ). 29 This value is also comparable to those of state-of-the-art COFs, including TPB-DMTP-COF (6.26 g g −1 ), 15 c iCOF-AB-50 (10.21 g g −1 ), 30 COF-TAPT (8.61 g g −1 ), 31 JUC-561 (8.19 g g −1 ), 32 TFB–DB COF (6.40 g g −1 ), 33 QTD-COF-V (6.29 g g −1 ), 34 SCU-COF-2 (6.00 g g −1 ), 35 and TFPB-PyTTA-COF (5.60 g g −1 ).…”

Polymorphic Covalent Organic Frameworks: Molecularly Defined Pore Structures and Iodine Adsorption Property

“…To address this challenging issue, it is, therefore, necessary to adjust the pore structure and morphology of COFs by controlling the stacking form [ 36 , 37 , 38 , 39 , 40 ] or introducing flexible building blocks [ 41 , 42 , 43 , 44 ]. In this case, the twisted pore structure, rather than the perfectly straight structure, can efficiently expose the adsorption site while hindering the desorption process of iodine molecules, thus leading to the maximum adsorption capacity [ 42 , 43 , 45 , 46 ]. Therefore, it is highly appealing to design a COF with a molecularly defined pore structure for efficient iodine adsorption.…”