Multivariate MOF-303/MIL-160 balancing the trade-off between capacity and selectivity in CO2/CH4 separation

Abstract

Porous adsorbents with high capacity and selectivity are recognized as promising alternatives for energy-efficient gas separation, but the inherent trade-off between the two metrics hinders their industrial application. Herein, we synthesize a multivariate Al-based metal–organic framework (MOF), namely MOF-303/MIL-160, for CO₂/CH₄ separation under the guidance of reticular chemistry. The obtained MOF-303/MIL-160 contains both 3,5-pyrazoledicarboxylic acid, the ligand of MOF-303, and 2,5-furandicarboxylic acid, the ligand of MIL-160, in a ratio of 1 : 0.51. MOF-303 exhibits high capacity but low selectivity, whereas MIL-160 shows the opposite. Multivariate MOF-303/MIL-160 draws upon their respective strong points, realizing the balance of trade-off between capacity and selectivity in CO₂/CH₄ separation.