Optimizing Pore Size and Polarity in Halogen-Functionalized Metal-Organic Frameworks for Efficient Xenon/Krypton...

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• High-purity xenon (Xe) is essential for semiconductor manufacturing and medical imaging.
• Separating trace krypton (Kr) from Xe is challenging due to their similar physical and chemical properties.
• Conventional gas separation techniques are inadequate for effective Xe/Kr separation.

Purpose of the Study:

• To design and synthesize novel metal-organic framework (MOF) materials for efficient Xe/Kr separation.
• To investigate the impact of halogen-functionalized ligands on MOF pore size and polarity for gas adsorption.
• To establish a structure-property relationship for optimizing Xe/Kr separation performance.

Main Methods:

• Synthesis of a series of halogen-functionalized MOFs (LIFM-DMOF-X$_{1}$, X = F, Cl, Br, I).
• Gas adsorption experiments to evaluate Xe/Kr separation performance and selectivity.
• Theoretical calculations (e.g., DFT) to analyze Xe interactions within the MOF structures.

Main Results:

• LIFM-DMOF-Cl$_{1}$ and LIFM-DMOF-Br$_{1}$ demonstrated excellent adsorption capacity and selectivity for Xe over Kr.
• The functionalized ligands effectively tuned MOF pore size and polarity, enhancing Xe uptake.
• Theoretical analysis confirmed stronger interactions between Xe and MOF components (C-H groups and halogens).

Conclusions:

• Halogen-functionalized MOFs provide a synergistic strategy for efficient Xe/Kr separation.
• The developed MOFs show significant potential for industrial applications requiring high-purity xenon.
• This research offers a pathway for designing tailored adsorbent materials for challenging gas separations.