Fabrication of ZnO–polysulfone solid-state composite membrane for water purification applications

Abstract

The increasing exploitation of water resources and the growing scarcity of clean water have pushed the trajectory of research to clean water generation techniques. In the given study, a novel Polysulfone and Zinc Oxide (PSf@ZnO) thin film composite membrane is presented for the removal of heavy metal ions from wastewater. The membrane was fabricated using the phase inversion technique and subsequently surface-modified with ZnO nanoparticles to enhance its chemical stability and filtration performance. FESEM, FTIR, XRD, and TGA were the characterization techniques employed to examine the membrane’s morphology, chemical structure, crystallinity, and thermal degradation. The concentrations of heavy metal ions Pb²⁺, Cu²⁺, Cd²⁺, Cr⁶⁺, and Ni²⁺ using atomic absorption apectroscopy (AAS) were analyzed. The results show that ZnO nanoparticles spread evenly throughout the polysulfone matrix. The ZnO modification improves surface hydrophilicity and surface wettability, leading to enhanced filtration efficiency by reducing pore blockage and promoting more uniform surface transport behavior. Thermal tests (TGA/DTA) show the membrane stands up better to heat and resists breaking down. When it comes to removing heavy metal ions, the membrane works remarkably well across the tested range, as long as conditions are suitable. Additionally, ZnO brings strong antibacterial properties, which helps the membrane fight off fouling and keeps it running longer. In conclusion, these findings point to the PSf@ZnO composite membrane as a cost-effective and sustainable option for water purification. The ZnO nanoparticles push its performance, making it an apt choice for both environmental and industrial uses.