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Item Fabrication of TiO2@ZIF-67 metal organic framework composite incorporated PVDF membranes for the removal of hazardous reactive black 5 and Congo red dyes from contaminated water(Elsevier B.V., 2024) Prabhakar, N.; Isloor, A.M.; Padaki, M.; Fauzi Ismail, A.Novel application of TiO2@ZIF-67 composite incorporated poly (vinylidene fluoride) (PVDF) mixed matrix flat-sheet membranes for treating the water contaminated with hazardous reactive black 5 and congored dyes was the crux of this work. The composite was characterized by FTIR, BET, XRD, zeta potential and particle size, and TGA. The as-synthesized composite was embedded in the PVDF polymeric matrix and flat-sheet-membranes were fabricated adopting the NIPS method followed by the different characterizations like scanning electron microscopy, EDS, elemental mapping, contact angle, atomic force microscopy, surface energy, and XPS. Results of the performance studies showed an enhanced pure water permeability from 150.99 Lm-2h?1 for neat membrane to 261.39 Lm-2h?1 for TZM-2. The reactive black 5 dye was rejected in 97.4 %, 92.2 %, and 84.84 % in acidic, basic and neutral conditions respectively by TZM-2 membrane. Whereas, the PVDF membranes without the composite showed rejections of 83.19 %, 82.5 %, and 72.1 % respectively in acidic, basic, and neutral conditions. The Congo Red dye was rejected in 89.4 %, 95.68 %, and 92.4 % in acidic, neutral and basic conditions respectively by TZM-2 membranes. Whereas, the PVDF membranes without the composite showed rejections of 82.8 %, 91.9 %, and 85.4 % respectively in acidic, neutral and basic conditions. © 2024Item Fabrication and incorporation of MIL-53(Fe)-zwitterionic brushes into PVDF thin film composite membranes for enhancing heavy metal/dye rejection from aqueous body(Elsevier B.V., 2025) Prabhakar, N.; Isloor, A.M.; Farnood, R.; Fauzi Ismail, A.The bioaccumulation of heavy metal ions is a serious concern for researchers. The dyes and heavy metal ions also aquatic life impacting the biodiversity adversely. Synthesis of novel MIL-53(Fe)-PSBMA particles, and its incorporation into PVDF-based thin-film composite membranes is the crux of this work. Firstly, H2N-MIL-53(Fe) was synthesized by metal displacement reaction which was then modified into MIL-53(Fe)-PSBMA brushes. The brushes were synthesized by atom transfer radical polymerization method. The amine groups of the NH2-MIL-53(Fe) help connecting the MOF to the polymeric moiety. The as-synthesized material and the fabricated TFCs were characterized by BET, FTIR, XRD, XPS, TGA, AFM, FE-SEM, zeta potential, and DLS particle sizer. The presence of sulphur groups on the XPS spectrum of modified MOF ensured the successful polymer grafting on it. Zwitterionic moieties have both positive and negative charges within a single molecule which gave a resultant zeta potential of ?13.1 mV for the brushes. A pure water flux of 26.32 Lm?2 h?1 and 97.33 %, 95.19 %, 82.06 %, and 78.47 % rejections for Pb2+, Hg2+, As3+, Cd2+ ions and 96.23 % and 94.04 % rejection for 100 ppm reactive black-5 and sunset yellow dyes respectively were obtained for the optimized membrane having 0.035 wt% loading of zwitterionic MOF. This result was attributed to the enhanced membrane hydrophilicity which was also correlated with contact angle and water uptake studies. © 2024 Elsevier B.V.Item Sustainable waste water purification via integration of novel COF@UiO-66 dual-layer PVDF/PEI hollow fiber membranes(Elsevier B.V., 2025) Prabhakar, N.; Isloor, A.M.; Othman, M.H.D.; A.F., A.F.In the present study, dual-layer (polyvinylidene fluoride (PVDF)/ polyether imide (PEI) blend membranes were fabricated by coextrusion technique, with varying loadings (0–1.5 wt%) of covalent organic framework (COF) grafted UiO-66, for dye and heavy metal ion removal. UiO-66-NH2 was chosen for its excellent surface area and water stability, which can enhance the water permeability through the membrane without getting degraded over a period of time. The structures of the synthesized UiO-66-NH2 and COF@UiO-66 were confirmed by characterizations like scanning electron microscopy (SEM), FTIR (Fourier Transform Infrared Spectroscopy), and XRD (X-ray Diffraction). The membrane fabricated with the synthesized additive in the outer layer, was characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM) for the surface topography and morphology. The incorporation of the additive significantly affected the hydrophilicity, porosity, and surface area of the membrane, resulting in improved permeability and rejection, along with imparting relatively good antifouling nature to the membrane. Membrane with outer dope flow rate of 2 mL/min and an optimized loading of the additive (1.0 wt.%) displayed a water permeability of 117.5 Lm?2 h?1 bar?1, whereas the neat membrane showed only 60 Lm?2 h?1 bar?1. The dyes, Congo red and reactive black-5, showed rejections of 99.1 %, and 97.96 % respectively. Whereas, the heavy metal ions mercury and lead showed 69.58 %, and > 99.9 % in the complexed state with humic acid for the optimized membrane, along with a bovine serum albumin (BSA) fouling rejection ratio of 74.22 %. Whereas the neat membrane without the MOF additive showed 89 %, 79 %, 75 %, and 43 % rejections for reactive black 5, congo red, lead, and mercury ions, respectively, with an FRR of only 57 %. © 2025 Elsevier B.V.