Interface engineering of 2D V2C MXene/APTES modified PVDF membranes with enhanced hydrophilicity, permeability, and antifouling properties for methylene blue removal

Poly(vinylidene fluoride) (PVDF) membranes are widely used in water purification because of their chemical resistance and thermal stability, but their hydrophobic nature makes them prone to fouling and limits water permeability. In this study, PVDF membranes were modified with vanadium carbide (V2C) MXene and 3-aminopropyltriethoxysilane (APTES)-V2C to address these shortcomings. V2C was selected due to its layered structure, conductivity, and hydrophilic surface chemistry, while APTES was introduced to stabilize the MXene and add functional groups that improve compatibility and antifouling behavior. In the 120-min filtration test, the modified membranes showed clear improvements compared to pristine PVDF. The addition of 2 wt% V2C in PVDF/V2C 2% (MMV2) reduced the water contact angle from 73° to 46° (MMV2), increased pure water flux from 20.99 m−2h−1 (PVDF) to 91.44 L m−2h−1 (MMV2), dye removal efficiency from 88.30 (PVDF) to 96.51% (MMV2), and recovery ratio from 58.2% (PVDF) to 84.4% (MMV2). With APTES functionalization (MMV2A-2), the removal efficiency reached 97.77% and flux recovery ratio improved markedly to 93.8% (MMV2A-2), indicating excellent resistance to fouling. These results confirm that V2C and its APTES-modified form were effective fillers for tailoring PVDF membranes, providing both higher permeability and stronger antifouling properties. The fabricated membranes fell within the ultrafiltration (UF) classification, as confirmed by molecular weight cut-off (MWCO) values of 52.2–77.6 kDa. The approach offered a practical route to improve PVDF membranes for dye removal and related ultrafiltration processes.