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.