Tetralactam Macrocycle-Based Polymers for Efficient and Rapid Adsorption of Radioactive Iodine
The release of radioactive iodine from nuclear accidents and nuclear medicine poses significant environmental and health risks. Here, we report the design and synthesis of two cross-linked macrocycle-based porous organic polymers (P1 and P2) with different functionalities for efficient and rapid capture of radioactive iodine. P1 achieves complete iodine adsorption within 5 minutes, with an exceptional adsorption rate constant (k_obs) of 18.92 g g−1 min−1 (8.24 g g−1 min−1 for P2), representing a record-high iodine removal rate among state-of-the-art porous organic polymers. P1 demonstrates superior iodine adsorption efficacy in dynamic flow-through experiments, achieving a remarkable efficiency of 96.4% for radioactive 131I removal, greatly minimizing radiation contamination. Experimental and modelling techniques reveal that the superior iodine adsorption performance originates from electron-rich functional groups, hydrophobic surface, and porous structure of P1, thus exhibiting remarkable iodine capture capabilities through charge transfer, halogen bonding, and hydrophobic effects. The adsorbents show excellent stability and performance under complex and harsh conditions (pH 2–10) and can be easily regenerated, confirming their excellent reusability and potential for practical applications.