1e:T4fe,The cryogenic separation of noble gases is energy-intensive and expensive, especially when low concentrations are involved. Metal-organic frameworks (MOFs) containing polarizing groups within their pore spaces are predicted to be efficient Xe/Kr solid-state adsorbents, but no experimental insights into the nature of the Xe-network interaction are available to date. Here we report a new microporous MOF (designated SBMOF-2) that is selective toward Xe over Kr under ambient conditions, with a Xe/Kr selectivity of about 10 and a Xe capacity of 27.07 wt % at 298 K. Single-crystal diffraction results show that the Xe selectivity may be attributed to the specific geometry of the pores, forming cages built with phenyl rings and enriched with polar -OH groups, both of which serve as strong adsorption sites for polarizable Xe gas. The Xe/Kr separation in SBMOF-2 was investigated with experimental and computational breakthrough methods. These experiments showed that Kr broke through the column first, followed by Xe, which confirmed that SBMOF-2 has a real practical potential for separating Xe from Kr. Calculations showed that the capacity and adsorption selectivity of SBMOF-2 are comparable to those of the best-performing unmodified MOFs such as NiMOF-74 or Co formate.1f:T4d6,Used nuclear fuel reprocessing represents a unique challenge when dealing with radionuclides such as isotopes of ⁸⁵Kr and ¹²⁹I₂ due to their volatility and long half-life. Efficient capture of ¹²⁹I₂ ( t_1/2 = 15.7 × 10⁶ years) from the nuclear waste stream can help reduce the risk of releasing I₂ radionuclide into the environment and/or potential incorporation into the human thyroid. Metal organic frameworks have the reported potential to be I₂ adsorbents but the effect of water vapor, generally present in the reprocessing off-gas stream, is rarely taken into account. Moisture-stable porous metal organic frameworks that can selectively adsorb I₂ in the presence of water vapor are thus of great interest. Herein, we report on the I₂ adsorption capacity of two microporous metal organic frameworks at both dry and humid conditions. Single-crystal X-ray diffraction and Raman spectroscopy reveal distinct sorption sites of molecular I₂ within the pores in proximity to the phenyl- and phenol-based linkers stabilized by the I···π and I···O interactions, which allow selective uptake of iodine.20:T710,

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