Deposition\nof Imidazole into Mesoporous Zirconium\nMetal–Organic Framework for Iodine Capture

Efficient capture of radioiodine is essential for the\nprotection\nof the ecological environment and the sustainable development of nuclear\nenergy generation. Metal–organic frameworks (MOFs) and their\nderivatives provide alternative potential for overcoming the limitations\nof traditional iodine adsorbents. Herein this work, imidazole (Im)\nis dispersed into a robust mesoporous zirconium MOF <b>PCN-222</b> by the heat deposition method, forming a high-uniformity composite <b>Im@PCN-222</b>. The large pore size and marked chemical resistance\nskeleton of <b>PCN-222</b> allow the incorporation of Im to\nreach 43 wt % while surviving the chemical corrosion of activated\nIm. The nearly saturated loading of Im significantly benefits the\nsorption capability toward iodine and gives rise to an exceptional\nadsorption capacity of 10.04 g g<sup>–1</sup> and excellent\nrecyclability. This value is higher than that of most of the MOFs\nand their derivatives. Further, Im was also successfully deposited\nonto the <b>PCN-222</b> functionalized porous Al<sub>2</sub>O<sub>3</sub> ceramic filtration membrane, which endowed the hybrid\nmembrane with efficient iodine sorption and separation properties.\nThis work highlights a new strategy for the fabrication of the MOF-based\nradioiodine adsorption composite as well as MOF composite-based filters.