Boosting radioactive iodine capture of microporous polymers through strengthened host–guest interaction

Abstract

Abstract Conjugated Microporous Polymers (CMPs) with strong host−guest interactions are promising adsorbents for decontamination of radioactive iodine pollutants, but the relationship between molecular structure and iodine capture performance is not well understood till now. Herein, we report a strategy to promote affinity of cost-effective and stable CMPs towards iodine contaminants through achieving a synergistic effect between the surface polarity and electron density, targeting a strong but reversible capture toward iodine species. The polymeric networks obtained through the coupling chemistry of cyanuric chloride and carbazole (denoted as CCBCB-CMP), presented an attractive adsorption capacity per unit BET specific surface area (11.56\xa0wt/(m2/g)), which is 15 times that of a reference nitrogen-free one (Py-CMP) and surpasses most known counterparts. Furthermore, our CMPs can remove iodine efficiently from the solutions and are easily recovered in at least three consecutive runs through simple extraction. Our work verifies the viability of enhancing host−guest interaction through optimizing the dipole moment and electron density of the building blocks, which would facilitate the design of high-performance scavengers for removing radioactive pollutants.