Functionalized Ionic Porous Organic Polymers Exhibiting High Iodine Uptake from Both the Vapor and Aqueous Medium

Abstract

Large-scale generation of radioactive iodine (129I, 131I) in nuclear power plants pose a critical threat in the event of fallout, thus rendering the development of iodine sequestering materials (from both the vapor and aqueous medium) highly pivotal. Herein, we report two chemically stable ionic polymers containing multiple binding sites, including phenyl rings, imidazolium cations, and bromide anions, which in synergy promote adsorption of iodine/triiodide anions. In brief, exceptional iodine uptake (from the vapor phase) was observed at nuclear fuel reprocessing conditions. Furthermore, the ionic nature propelled removal of >99% of I3 – from water within 30 min. Additionally, benchmark uptake capacities, as well as unprecedented selectivity, were observed for I3 –anions. The excellent affinity (distribution coefficient, ∼105 mL/g) enabled iodine capture from seawater-spiked samples. Moreover, iodine-loaded compounds showed conductivity (10–4 S/cm, 10–6 S/cm), placing them among the best known conducting porous organic polymers. Lastly, DFT studies unveiled key insights in coherence with the experimental findings.

Ionic Functionalization of Multivariate Covalent Organic Frameworks to Achieve an Exceptionally High Iodine‐Capture Capacity

“…[13a,c, 14] In principle,C OFs can be functionalized with the desired adsorption active sites (e.g., ionic sites) through the design of appropriate monomers or post-synthesis modification to achieve high I 2 adsorption capacity. [15] However,i n practice,i ti sv ery challenging to incorporate ionic sites into COFs while maintaining high crystallinity and porosity.T he "multivariate" strategy,b ased on the use of two or more structurally homologous monomers to simultaneously incorporate multiple groups into the COF structure,p rovides additional flexibility for functionality engineering. [14a, 16] The few successful examples of ionic COFs were synthesized using the "multivariate" strategy combined with subsequent surface reactions;h owever, these COFs were not tested for I 2 capture.…”

Porous polyaminoamides via an exotemplate synthesis approach for ultrahigh multimedia iodine adsorption

“…14,38,39 Rarely a material is reported that demonstrated iodine adsorption in all different media which include vapor phase, organic phase and aqueous phase. 40 Besides that in most cases, the iodine adsorption ability in the organic phase and water is lower and demands improvement.…”

Ionic Functionalization of Multivariate Covalent Organic Frameworks to Achieve an Exceptionally High Iodine‐Capture Capacity

“…[13] Thec rystallinity of COFs provides aw elldefined porosity and full accessibility to active sites in the framework, which are beneficial for many applications in [*] Dr.Y .Xie, Dr.T .Pan, Dr.Q.Lei, Dr.C.Chen, Dr.X.Dong, Dr.J.Shen, Prof. Dr. [13a,c, 14] In principle,C OFs can be functionalized with the desired adsorption active sites (e.g., ionic sites) through the design of appropriate monomers or post-synthesis modification to achieve high I 2 adsorption capacity. [15] However,i n practice,i ti sv ery challenging to incorporate ionic sites into COFs while maintaining high crystallinity and porosity.T he "multivariate" strategy,b ased on the use of two or more structurally homologous monomers to simultaneously incorporate multiple groups into the COF structure,p rovides additional flexibility for functionality engineering. [14a, 16] The few successful examples of ionic COFs were synthesized using the "multivariate" strategy combined with subsequent surface reactions;h owever, these COFs were not tested for I 2 capture.…”