Novel pyrazole-based MOF synergistic polymer of intrinsic microporosity membranes for high-efficient CO2 capture

Advanced membranes with high gas separation performances are highly demanded for energy-efficient CO2 capture. Nonetheless, the ubiquitous “trade-off” relation between permeability and selectivity remains a daunting challenge for currently synthetic membranes. Here, a novel category of pyrazole-based MOF (termed as MOF-303 or Al(OH)HPDC) as nanofillers was firstly blended into the polymer of intrinsic microporosity (PIM-1) matrix to fabricate MOF-303/PIM-1 mixed matrix membranes (MMMs). Owing to their superiorities of CO2-philic ability, high porosity and suitable aperture sizes, the presence of MOF-303 in membrane could create additional CO2 transport nanochannels, thus promoting the rapid transport of CO2 molecules across the blended membrane. As a result, this newly-developed membrane containing 10 wt% MOF-303 nanofilles evince a remarkably high CO2 permeability of 6602.8 Barrer, with a comparably ideal CO2/N2 selectivity of 25.6. This corresponding separation performance far surpasses the most popular 2008 Robeson's upper bond, and approaches the refined 2019 Robeson's upper bond. This study may provide a novel avenue to apply pyrazole-based MOFs in fabricating the facilitated transport membranes applied in industrial CO2 capture.