Understanding the transport mechanism of seawater through FMOF-1 and its derivative via molecular dynamics simulation

Molecular modeling of thin-film nanocomposite membranes for reverse osmosis water desalination

“…The remarkable water permeability was attributed to the enriched hydrophilic surface sites provided by molybdenum. 106 Two MOF-based membranes also exhibited good performance under moderate pressure (10–250 MPa): functionalized (with –CH 3 ) and non-functionalized single-layer FMOFs (pore diameter of 6.1 Å) 193 and double-layer HAB-MOFs functionalized with Nickel and Copper (pore diameter of 8 Å). 151 Strong interactions between water molecules and the –CH 3 functional groups caused increased water flux in FMOF membranes.…”

“…Chen et al 193 demonstrated fluorous metal–organic frameworks (FMOFs) functionalized by the CF 3 group as a new class of MOFs with adequate pore size and excellent stability in a hydrated environment. The proposed CF 3 -FMOF membrane achieved 95% salt rejection (calculated via eqn (6)) and high water permeability of 674 L m −2 h −1 bar −1 which is orders of magnitude greater than that of commercial RO membranes (1.08–3.6 L m −2 h −1 bar −1 22 ).…”

“…19(a)) and hence suffered from the permeability–selectivity tradeoff. Considering the data for both water flux and salt rejection, the FMOF-1 membrane presented by Chen et al 193 and the bilayer Ni/Cu-HAB-MOF membrane designed by Cao et al 151 exhibited a combination of good water permeability and salt selectivity when the pressure difference was below 100 MPa.…”

“…Most of the TFNC membranes exhibit higher water permeability than commercial RO membranes and comparable salt rejection. Except for a few cases (large charged CNTs, 161 FMOF-CH 3 193 and bilayer graphene 182 ), 100% salt rejection is achieved and the difference among them lies in the water permeability. A few strategies for improving water permeability can be drawn from this comparison: (1) increasing the size of pores or nanochannels (Hong et al , 161 Cohen-Tanugi and Grossman, 150 Cohen-Tanugi et al , 182 Ang et al , 138 Li et al 176 ), (2) increasing hydrophilicity through functionalization (Cohen-Tanugi and Grossman, 150 Xu et al , 199 Heiranian et al , 106 Cao et al 151 ), (3) reducing the number of layers in 2D nanomaterial-based membranes and aligning the pores (Cohen-Tanugi et al , 182 Zhou et al 79 ), and (4) arranging nanofillers with specific structures, e.g.…”

Accelerating filtration by introducing an oscillation paradigm and its atomistic origin

“…1c, and the difference is that the CO functional group becomes the C–H functional group. The size of the simulation box in the x – y – z dimensions is 5.7 nm × 6.6 nm × 30.0 nm with the COF membrane located in the x – y plane, and the simulation box contains four parts, including a graphene piston applying pressure to the brine, a COF filter membrane, and brine containing sodium and chloride ions at a molar concentration of 0.5 M, 51–53 slightly lower than the salinity of seawater (∼35 g L −1 ). 54 The lower salinity was chosen because the concentration of water flowing into the pure water region would effectively increase the salinity of the seawater side during the simulation.…”