Biomimetic Hydrophobic‐Polar Metal‐Organic Frameworks for Record‐Breaking Separation and Capture of Xenon and Krypton
Yizhou Liu, Zhijie Zhou, Wei Xia, Zheng Fang, Zhiguo Zhang, Qiwei Yang, Qilong Ren, Zongbi Bao
Abstract
Abstract The separation and capture of xenon (Xe) and krypton (Kr) pose critical industrial and environmental challenges. We report two isostructural MOFs (NKMOF‐8‐Br and NKMOF‐8‐Me) with ultra‐micropores (∼6 Å) integrating bromine/methyl and cyano groups, creating biomimetic hydrophobic‐polar microenvironments for efficient Xe/Kr separation and nuclear off‐gas capture. These MOFs exhibit record low‐pressure Xe uptake and Xe packing density. Breakthrough tests under two industrial scenarios—air‐separation byproduct purification and trace gas capture—demonstrate unprecedented Kr productivity (12.26 mmol g −1 ) and Xe/Kr capture capacity (Xe: 32.13 mmol kg −1 ; Kr: 9.35 mmol kg −1 ), with retained performance after 500 kGy β ‐irradiation. Single‐crystal X‐ray diffraction confirms gas molecules preferentially occupying channel centers, stabilized by hydrophobic van der Waals interactions and cyano polarization effects, while theoretical simulations establish a clear structure‐property relationship. These results highlight NKMOF‐8‐Br and NKMOF‐8‐Me as leading candidates for energy‐efficient noble gas separation and nuclear waste management, and demonstrate a generalizable strategy for engineering adsorption through hydrophobic‐polar synergy.