Pore-Structure Control in Metal-Organic Frameworks (MOFs) for Capture of the Greenhouse Gas SF with Record Separation.

In the electronics industry, the efficient recovery and capture of sulfur hexafluoride (SF ) from SF /N mixtures is of great importance. Herein, three metal-organic frameworks with fine-tuning pore structures, Cu(peba) , Ni(pba) , and Ni(ina) , were designed for SF capture. Among them, Ni(ina) has perfect pore sizes (6 Å) that are comparable to the kinetic diameter of sulfur hexafluoride (5.2 Å), affording the benchmark binding affinity for SF gas. Ni(ina) exhibits the highest SF /N selectivity (375.1 at 298 K and 1 bar) and ultra-high SF uptake capacity (53.5 cm  g at 298 K and 0.1 bar) at ambient conditions. The remarkable separation performance of Ni(ina) was verified by dynamic breakthrough experiments. Theoretical calculations and the SF -loaded single-crystal structure provided critical insight into the adsorption/separation mechanism. This porous coordination network has the potential to be used in industrial applications.