A Tailor-Made Interpenetrated MOF with Exceptional Carbon-Capture Performance from Flue Gas

Abstract

Summary Metal-organic frameworks (MOFs) have attracted significant attention as sorbents for low-energy separation of CO2 from flue gas. Herein, we report the use of an interpenetration approach to developing a fluorinated MOF with the appropriate pore system to enable the efficient capture of CO2 from flue gas at 298 K. The MOF, dptz-CuTiF6, exhibits excellent volumetric and gravimetric CO2 uptakes at 10% CO2 and 298 K, which are superior to those of the reference aqueous amine technique, with significantly lower energy input for regeneration (38 kJ mol−1 versus 105 kJ mol−1). In cyclic breakthrough experiments, dptz-CuTiF6 achieves complete CO2 desorption at 298 K under inert gas purging. Single-crystal X-ray diffraction studies demonstrate that the exceptional CO2 adsorption capacity, moderate CO2 heat of adsorption, and high CO2-N2 selectivity are due to the optimal packing of the CO2 molecules within the MOF as well as the favorable thermodynamics and kinetics from cooperative host-guest interactions.