An anionic metal-organic framework constructed from a triazole-functionalized diisophthalate featuring hierarchical cages for selective adsorptive C2H2/CH4 and CO2/CH4 separation

作者：Liu, Zhen; Lv, Lingzhi; He, Yabing^*; Feng, Yunlong^*

来源：CrystEngComm, 2017, 19(20): 2795-2801.

DOI：10.1039/c7ce00661f

• LANTHANIDE COORDINATION POLYMERS
• ZEOLITIC IMIDAZOLATE FRAMEWORKS
• CARBON-DIOXIDE CAPTURE
• FINELY TUNING MOFS
• LEWIS BASIC SITES
• HIGH-PERFORMANCE
• PORE-SIZE
• LIGHT-HYDROCARBONS
• ACETYLENE UPTAKE
• UPTAKE CAPACITY

Exploring organic linkers is very important to target porous metal-organic frameworks with desired structures and properties. In this work, we devised a triazole-functionalized bent diisophthalate ligand, 5,5'(triazole-2,5-diyl) diisophthalate (H4L), which was used to successfully construct an anionic copper-based MOF ([Cu-6(L)(3)(H2O)(4)(HCOO)].Me2NH2+.20DMF) under solvothermal reaction conditions. Single-crystal X-ray diffraction analyses reveal that the title MOF compound features three types of polyhedral cages with different shapes and sizes. More importantly, the title MOF compound after desolvation exhibits promising potential for industrially important C2H2/CH4 and CO2/CH4 separations. At 298 K and 1 atm, the C2H2 and CO2 uptakes reach 107.6 and 65.6 cm(3) (STP) g(-1), respectively. The adsorption selectivities are predicted to be 33.4-120.3 for an equimolar C2H2-CH4 gas mixture and 6.4-7.6 for an equimolar CO2-CH4 gas mixture at 298 K and pressures varying from 1 to 109 kPa. The highly selective adsorption of C2H2 and CO2 over CH4 might be attributed to the synergistic interplay between suitable pore sizes, functional active sites, such as open metal sites and Lewis basic nitrogen atoms in the pore surface, and the ionic nature of the framework.

• 出版日期2017-5-28
• 单位浙江师范大学