Amine-functionalized MOFs@GO as filler in mixed matrix membrane for selective CO2 separation

UiO-66-NH 2 @GO nanoparticles were synthesized by growing UiO-66-NH 2 on graphene oxide (GO) nanosheets. The obtained nanoparticles were incorporated in polyimide (PI) matrix to improve the CO 2 separation performance. The crystalline structure, interaction between UiO-66-NH 2 and GO and the dispersion of UiO-66-NH 2 @GO were characterized by various techniques. Owning to the interaction between UiO-66-NH 2 and GO, UiO-66-NH 2 nanocrystals were well-anchored on GO sheets and the size was tailored. Also, it can be found that the high-aspect GO nanosheets in polymer matrix improved the dispersion of UiO-66-NH 2 nanoparticles. The high porosity of UiO-66-NH 2 @GO and inherent adsorption property to CO 2 significantly enhanced the gas separation performance of composite membranes compared to pristine PI membrane. The developed UN@GO-PI mixed matrix membrane with 5 wt% of UiO-66-NH 2 @GO loading showed excellent and stable CO 2 /N 2 separation performance with the CO 2 permeability of 7.28 Barrer and the CO 2 /N 2 selectivity of 52.