TEOS-modified ZnO nanoparticles polyethersulfone nanocomposite membranes for wastewater

In the present study, Tetraethoxysilane (TEOS)-functionalized zinc oxide nanoparticles (ZnO NPs) were fabricated and used to develop innovative polyethersulfone (PES) nanocomposite membranes with antibacterial properties for wastewater treatment. ZnO NPs were incorporated at different concentrations (0 to 0.9 wt.%) into the membrane matrix. To evaluate the membranes’ characteristics and performance, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), pore size and contact angle measurements, and field-emission scanning electron microscopy (FESEM) were employed. The results showed that incorporating the modified NPs enhanced the membranes’ surface properties through improved morphology and hydrophilicity. Specifically, the contact angle decreased from 67.5° for the pristine membrane to approximately 46° for the membrane containing 0.6 wt.% TEOS-modified ZnO NPs. The mean pore size and porosity also increased with nanoparticle loading, thereby enhancing membrane permeability. At the optimal loading of 0.6 wt.%, the pure water flux increased significantly from 105.5 to 192.3 L m−2 h−1 while maintaining high bovine serum albumin (BSA) rejection above 88%. Moreover, the membranes exhibited improved antifouling performance, with the flux recovery ratio increasing to 90.37%. Additionally, the ZnO NP-modified nanocomposite membranes demonstrated excellent antibacterial activity against Staphylococcus aureus and Escherichia coli.