Pore Environmental Modification by Amino Groups in Robust Microporous MOFs for SF6Capturing and SF6/N2Separation

Capturing and separating the greenhouse gas SF6from nitrogen N2have significant greenhouse mitigation potential and economic benefits. We used a pore engineering strategy to manipulate the pore environment of the metal–organic framework (MOF) by incorporating organic functional groups (−NH2). This resulted in an enhanced adsorption of SF6and separation of the SF6/N2mixture in the MOF. The introduction of amino (−NH2) groups into YTU-29 resulted in a reduction of the Brunauer–Emmett–Teller surface but an increase in interactions with SF6within the confined pores. Water-stable YTU-29-NH2showed a significantly higher SF6uptake (95.5 cm3/g) than YTU-29 (77.4 cm3/g). The results of the breakthrough experiments show that YTU-29-NH2has a significantly improved separation performance for SF6/N2mixtures, with a high SF6capture of 0.88 mmol/g compared to 0.56 mmol/g by YTU-29. This improvement is due to the suitable pore confinement and accessible −NH2groups on pore surfaces. Considering its excellent regeneration ability and cycling performance, ultrastable YTU-29-NH2demonstrates great potential for SF6capturing and SF6/N2separation.