Sulfur hexafluoride (SF6) is the most potent greenhouse gas whose emission is in great need of reducing during the indus-trial processes. Here, a variety of covalent organic frameworks with varying topologies, surface areas, pore size distribu-tions is designed and synthesized for systematically studying structure-property relationships of COF-based SF6 adsor-bents. Surface area was found to be a prerequisite for achieving high SF6 uptakes, and small pore size at ca. 0.9 nm could effectively enhance the adsorbate-adsorbent interaction and hence the SF6/N2 selectivity. With a large specific surface area and a suitable pore size, RCOF-1 showed superior SF6 adsorption capacities up to 4.13 mmol g-1 and large SF6/N2 se-lectivity up to 125 (273 K, 100 kPa), which can be considered one of the most high-performance porous materials for SF6 capture and separation. This work not only provides a series of high-performance SF6 adsorbents, but also broadens the horizon of applications of the emerging COFs, pointing out their development direction in the field of SF6 capture and separation.
Supporting Information_Microporous covalent organic frameworks for sulfur hexafluoride uptake and separation
materials and instruments, experiments and methods, SEM, FTIR, PXRD and structural simulations, BET plots, TGA, pore size distributions, N2 sorption isotherms