Selective SF₆/N₂ Separation with High Uptake Under Low Pressures by Stable Al-MOF

Efficient and economical capture and separation of sulfur hexafluoride (SF₆) are critical for emissions mitigation and industrial reuse. Conventional distillation methods remain energy-intensive, prompting the need for cost-effective alternatives. Here, MOF-303, constructed from earth-abundant aluminum and low-cost linkers, features optimally sized pores (8.3 Å) that selectively adsorb SF₆ (5.5 Å) over N₂ (3.6 Å). This rational pore engineering enables MOF-303 to achieve benchmark SF₆ capture (1.91 mmol g^-1 at P < 0.1 bar) with exceptional selectivity (148), while its low regeneration energy (22.9 kJ mol^-1) ensures practical cycling. Breakthrough experiments confirm robust performance under dynamic conditions. Computational studies reveal how pore geometry enables size-exclusive recognition. Compared to noble-metal adsorbents, MOF-303's earth-abundant components reduce costs by >70%, offering a sustainable solution for industrial SF₆ recovery.