Tailoring Electron-Rich Fluorescent Supramolecular Organic Frameworks for Efficient Capture and Visual Monitoring of Iodine

The efficient capture and monitor of radioactive iodine are crucial for managing radioactive nuclear waste and protecting human health. Herein, three metal–organic coordination compound-mediated supramolecular organic frameworks (MSOFs) are reported with distinct electron-rich structures for efficient iodine capture with fluorescence response. The electron-rich adsorption sites play crucial roles for electron-deficient iodine capture via charge transfer interactions, where π donors contribute greater than nitrogen heteroatom. Among three MSOFs, MSOF-3 with the maximum numbers of electron-rich π donors exhibited the highest iodine uptake capacity (3.70 g mmol⁻¹). Prominently, the charge transfer interactions between iodine and MSOFs result in distinct fluorescence response during iodine uptake, establishing a real-time fluorescence monitoring system. To facilitate the personal health protection toward practical application, a mask with high iodine removal efficiency (99.1%) and real-time fluorescence response is successfully developed. This study underscores the great promise of electron-rich fluorescent MSOFs for capture and sensing of radioactive iodine, offering substantial prospects for the advance of protective equipment in the nuclear industry.