Dichloromethane-knitting synthesis of fluorinated porous organic polymers for superior sulfur hexafluoride adsorption and separation

Sulfur hexafluoride (SF 6 ), a crucial gas in the power and semiconductor industries, presents significant challenges for recovery and separation. This work reports the synthesis of a series of porous organic polymers (POPs) with high porosity and physicochemical stability via a Lewis acid-catalyzed slow-knitting method. Different fluorinated organic monomers were employed, using dibromomethane (DBrM) as both solvent and electrophilic cross-linker. The resulting DBrM-knitted POPs exhibited BET surface areas up to 1,408.37 m 2 /g, surpassing those of chloroform-knitted POPs by 53.51 %-160.26 %. These materials demonstrated superior SF 6 adsorption capacity, tunable via the position of fluorine groups. The optimal material achieved an SF 6 adsorption capacity of 91 ml/g at 273 K and an SF 6 /N 2 separation selectivity of 195.70. An optimal pore size of 0.73 nm was identified for SF 6 adsorption and separation. These findings contribute significantly to the development of advanced porous materials for efficient SF 6 recovery.