Robust Metal–Triazolate Frameworks for CO₂ Capture from Flue Gas

Abstract

Construction of thermally and chemically robust metal-organic frameworks (MOFs) is highly desirable for postcombustion CO₂ capture from flue gas containing water vapor and other acidic gases. Here we report a strategy based on appending amino groups to the triazolate linkers of MOFs to achieve exceptional chemical stability against aqueous, acidic, and basic conditions. These MOFs exhibit not only CO₂/N₂ thermodynamic adsorption selectivity as high as 120 but also CO₂/H₂O kinetic adsorption selectivity up to 70, featuring distinct adsorptive sites at the channel center for CO₂ and at the corner for H₂O, respectively. The best performing MOF in this series features low regeneration energy, high CO₂ capture utility under humid conditions, and decent cycling performance for mimic flue gas.