Selective Carbon Dioxide Capture and Ultrahigh Iodine Uptake by Tetraphenylethylene-Functionalized Nitrogen-Rich Porous Organic Polymers
Susan Sen, Rasha Diab, Mohammad H. Al‐Sayah, Ribal Jabbour, Asif Equbal, Oussama M. El‐Kadri
Abstract
The development of efficient adsorbent materials capable of dual capture of carbon dioxide (CO 2 ) and iodine is of great importance due to the significant contribution of anthropogenic CO 2 to climate change and the potential risks associated with nuclear energy sources, such as the release of radioactive iodine during nuclear waste processing and accidents. In this study, two nitrogen-rich tetraphenylethylene-functionalized porous organic polymers were prepared via a Schiff-base condensation reaction between 4,4′,4″,4‴-tetra(2,4-diamino-1,3,5-triazin-6-yl)tetraphenylethene (TTPE) and 2-carboxaldehydefuran or 2-carboxaldehydethiophene to form aminal-linked triazine-based porous organic polymers, TTPEPOP-O and TTPEPOP-S, having high surface areas of 741 and 999 m 2 g –1, respectively. The synergetic effect of electron-rich nitrogen species, π-conjugated moieties, and microporosity of these polymers makes them promising adsorbents for effective CO 2 sequestration and iodine removal. TTPEPOP-O and TTPEPOP-S exhibit moderate CO 2 uptake of 2.34 and 2.94 mmol g –1, respectively, at 273 K and 1.0 bar, with high selectivity to CO 2 over N 2 and CH 4 under ambient conditions. In addition, the two polymers demonstrate ultrahigh iodine uptake capacity of over 400 wt % from the gas phase and can remove up to 99% of dissolved iodine from iodine-cyclohexane solution. Based on our findings, the ecofriendly (metal-free) nature of TTPEPOPs and their ability to capture both CO 2 and iodine make them promising potential materials for environmental remediation.