Covalent triazine-based frameworks (CTFs) from triptycene and fluorene motifs for CO₂adsorption

Abstract

Two microporous CTFs with triptycene (TPC) and fluorene (FL) have been synthesized through a mild AlCl3-catalyzed Friedel–Crafts reaction, with the highest surface area of up to 1668 m2 g−1 for non-ionothermal CTFs. CTF-TPC and CTF-FL show an excellent carbon dioxide uptake capacity of up to 4.24 mmol g−1 at 273 K and 1 bar.

Carbonization of covalent triazine-based frameworks via ionic liquid induction

“…Consequently, IAST can be confidently used to evaluate gas selectivity in KPOP-6b. The predicted separation factors of CO 2 /N 2 (10:90) and CO 2 /CH 4 (50:50) at 1 bar are 87.9 and 9.2 at 298 K, slightly lower than 101.2 and 11.5 at 273 K. The CO 2 /CH 4 selectivity is similar to the reported data but the predicted separation factor of CO 2 /N 2 selectivity is quite high among the CTFs materials compared to CTF-1 (20, 298 k), 12 bpim-CTF400 (32, 298 K), 44 and CTF-FL (48, 273 k), 45 but lower than few functionalized porous organic polymers like pym-CTF500 (502, 298 k), 46 and PPN-6-CH 2 DETA (442, 298 k). 47 In conclusion, we report a series of POPs with different pore sizes and surface areas by changing the ratio of the monomer and catalyst, via ionic liquid induced carbonization, a method that is different from the previously reported methodology by changing the reaction temperature.…”

“…Solid-state 13 C NMR spectra (Fig. 6) of KPOP-6a and KPOP6b, reveal two peaks located at 41.2 and 32.2 ppm that are attributed to the two kinds of carbon from adamantane core 38 , confirming the presence of adamantane moieties within the framework of KPOP-6a and KPOP-6b.…”

“…Infrared spectroscopy (IR), elemental analysis (EA), powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA) were used to study the composition of the materials which indicate that the carbonization of the frameworks happens due to the ionic liquid-induction. 13 C solid state NMR clearly shows the carbonization of the adamantane core. Although, it has been reported that microporous and mesoporous CTFs were obtained by tuning the reaction temperature, the associated mechanism has yet to be well understood and demonstrated.…”

“…6) of KPOP-6a and KPOP6b, reveal two peaks located at 41.2 and 32.2 ppm that are attributed to the two kinds of carbon from adamantane core 38 , confirming the presence of adamantane moieties within the framework of KPOP-6a and KPOP-6b. However, the solid-state 13 C NMR spectra collected on KPOP-6c, KPOP-6d, and KPOP6e, clearly show that the adamantane units were probably converted to amorphous carbon during the reaction process.…”

“…Porous organic polymers (POPs), an inorganic node free version of porous materials (including crystalline covalent organic frameworks (COFs), 6 and amorphous porous aromatic frameworks (PAFs), 7 polymers of intrinsic microporosity (PIMs), 8 porous polymer networks (PPNs), 9 covalent triazinebased frameworks (CTFs) [10][11][12][13][14][15][16][17][18][19] ) are attracting more and more attention because of their great potential for practical applications, for example, gas storage, separation, catalysis, and electronic device. 20 Among these materials, CTFs can be obtained by using a cheap catalyst such as ZnCl 2 and possess high chemical and thermal stability.…”