Pore Space Multi-Layer Functionalization Boosting Industrial Radioactive Iodine Capture with Record Capacity and...

Capturing radioactive molecular iodine (I₂) from nuclear waste under industrial conditions remains a considerable challenge. Herein, we developed for the first time a pore space multiple-layer functionalization (PSMLF) strategy, which enables directionally distribute functional sites across the multi-layer regions of large pore space, thereby enhancing the I₂ adsorption ability by optimizing pore space utilization. Utilizing this approach, the optimized adsorbent PAF-1-NTM achieves a record-high I₂ uptake of 88.58 wt% under simulated industrial conditions (150 °C and 150 ppmv I₂), a 108-fold improvement over its parent material, PAF-1. This performance significantly surpasses that of industrial Ag@MOR and all previously benchmarked adsorbents under the same conditions. Furthermore, adsorption kinetic of PAF-1-NTM (k₁ = 0.025 min^-1) are significantly higher than those of all other porous adsorbents reported to date. These results thus establish PAF-1-NTM as a new benchmark for high-temperature I₂ adsorbents. Mechanism investigation reveals a new insight that the I₂ adsorption capacity is positively correlated with the pore space utilization rate. Our work not only develops a promising adsorbent for industrial radioactive I₂ capture but also establishes a general design principle for creating high-temperature I₂ adsorbents suitable for practical applications.