Investigation of SIFSIX-3-Ni Membranes for CO₂/N₂ Separation

The pressing need to address climate change has necessitated the development of advanced technologies for CO2 separation and capture. Existing separation techniques including scrubbing and cryogenic distillation are often limited by scalability challenges and operational costs in contrast to membrane-based separations. Herein, we report the separation of CO2 from N2 using ultramicroporous SIFSIX-3-Ni MOF membranes. We investigated the influences of membrane composition and thickness on gas permeance and separation efficiency. SIFSIX-3-Ni membranes resulted in a CO2 permeance of 105.33 × 10–7 mol/m2 s Pa and a CO2/N2 selectivity of 8. Following up to 4 h of exposure to lab air, the SIFISX-3-Ni membranes did not show any decline in separation performance, confirming its stability. Comparison of membrane performances for 10, 20, 30, and 60 cycles further highlights the importance of synthesis optimization.