Novel integration of dual-modified Zr-MOFs and graphene oxide nanocomposites in polyethersulfone membranes: Enhanced permeability, selectivity, and fouling resistance

Designing and fabricating ultrafiltration membranes that possess relatively high permeability while simultaneously maintaining high rejection and improved antifouling properties continues to be a challenge. In this study, we investigated the integration of novel melamine modified Zr-based metal organic frameworks (Zr-MOFs) with nanosheets of graphene oxide (GO) and sulfonated graphene oxide (SGO). These composite materials were synthesized using the solvothermal process and subsequently coated onto the PES membrane surface using the vacuum-assisted dip-coating method. The stability enhancement of the topmost MOF composite layer adhering to the membrane surface is attributed to hydrogen bonding, π-π stacking, and van der Waals interactions. These effects are augmented by the incorporation of polar functional groups such as hydroxyl, carboxyl, sulfonate, and amine groups. The optimized composite membranes incorporating MOFs exhibit enhanced performance, with a permeability of 80.2    L/m 2   h   bar, achieving a bovine serum albumin (BSA) rejection of ≥97.8 % and a humic acid (HA) rejection of 98.9 %. Moreover, a flux recovery ratio (FRR) of 89.5 %. To investigate the interactions among the incorporated components, molecular dynamics (MD) simulations were employed in a computational study. The simulations validated hydrogen bond formation and reinforced prior studies, demonstrating the potential of Zr-MOF compositions as effective hydrophilic nanoparticles. The overall results indicate a substantial enhancement in membrane performance and underscore the high potential for practical applications.