Interface regulation of mixed matrix membranes by ultrathin MOF nanosheet for faster CO2 transfer

Molecularly Homogenized Composite Membranes Containing Solvent-Soluble Metallocavitands for CO2/CH4 Separation

“…On the contrary, the CO 2 /CH 4 selectivity declined from 20 to 13 for the pure 6FDA-DAM membrane. Thus, the plasticization effect induced by high pressure observed in the pure 6FDA-DAM membrane was significantly alleviated in the ZRA-2.2% membrane, which is likely due to the reduced mobility of 6FDA-DAM segments induced by the interactions between 6FDA-DAM chains and ZRA clusters . The alleviated plasticization effect may be originated from the strong affinity between the polymer and ZRA as mentioned above.…”

“…In addition, the aggregation of the additive, the decrease in the d-spacing value, and the formation of a more complex gas diffusion pathway caused by the high loading of filler may be responsible for the reduced permeability. 55 The results suggested that the optimal loading of ZRA was 2.2% for the MMMs made by DMA, which overcame the trade-off between permeability and selectivity of the pure 6FDA-DAM membrane. Similar results were obtained for the MMMs fabricated by DMF (Figure 6b), except that the MMMs made by DMF showed lower CO 2 permeabilities, for example, being ∼949 barrer when the ZRA loading was 2.2 wt %.…”

“…The d-spacing value variation of the tested membranes is in good accordance with the results of single-component gas permeation experiments. In addition, the aggregation of the additive, the decrease in the d-spacing value, and the formation of a more complex gas diffusion pathway caused by the high loading of filler may be responsible for the reduced permeability . The results suggested that the optimal loading of ZRA was 2.2% for the MMMs made by DMA, which overcame the trade-off between permeability and selectivity of the pure 6FDA-DAM membrane.…”

“…Thus, the plasticization effect induced by high pressure observed in the pure 6FDA-DAM membrane was significantly alleviated in the ZRA-2.2% membrane, which is likely due to the reduced mobility of 6FDA-DAM segments induced by the interactions between 6FDA-DAM chains and ZRA clusters. 55 The alleviated plasticization effect may be originated from the strong affinity between the polymer and ZRA as mentioned above. In other words, the presence of a small amount of ZRA in the polymer matrix largely contributed to the improvement of CO 2 permeability and the enhanced plasticization resistance for CO 2 /CH 4 separation.…”

Advances in metal–organic framework-based membranes

“…Similarly, 2D MOF nanosheets with even higher surface area to volume ratios exhibit huge potential in promoting fillerpolymer interactions in MMMs. 13,[176][177][178] Notably, the new trend of using 2D MOF nanosheets as fillers will be elaborately discussed in the following section. MOFs with desired particle size and morphology can be obtained by both bottom-up and top-down strategies.…”