A Metal‐Organic Framework with Tailored Shape‐Matched Interactions Towards Ambient‐Temperature Argon Removal for Oxygen Purification

High-purity oxygen (O₂) is essential for high-value-added applications in the medical, aerospace, and electronics sectors. The production of high-purity O₂ via non-thermal-driven pressure-swing adsorption has the advantages of portable operation and low energy consumption. However, effectively removing trace amounts of argon (Ar) impurities in this process is indispensable, and it is a fundamental challenge to achieve the preferential adsorption of inert Ar atoms over polar O₂ molecules instead of traditional thermodynamic or molecule sieving strategies. Herein, we have demonstrated this problem was addressed by integrating spheroidal shape-matched interactions to fit the spheroid Ar atoms while repulsing the linear O₂ molecules. Using this strategy, customized TYUT-20 enables the exceptional recognition of Ar atoms over O₂ molecules, demonstrating an unprecedented Ar adsorption capacity of up to 14.5 cm³ g^-1 and a top-performing Ar/O₂ (1.54) selectivity at 298 K and 1 bar. The Ar atom recognition mechanism on this adsorbent has been investigated using Ar-loaded single crystal diffraction analysis and molecular simulation studies. The productivity of high-purity O₂ (>99.99%) from a 5/95 Ar/O₂ mixture breakthrough experiment reached 6.6 L kg^-1 under ambient conditions, which highlighted TYUT-20 as a very promising adsorbent in ready-to-use high-purity O₂ production.