Incorporation of oleic acid-modified Ag@ZnO core-shell nanoparticles into thin film composite membranes for enhanced antifouling and antibacterial properties

In this study, Ag@ZnO-Oleic acid (OAc)/polyamide (PA) thin film nanocomposite (TFN) membranes were prepared by interfacial polymerization with dispersing hydrophobic Ag@ZnO-OAc core-shell nanoparticles in trimesoyl chloride (TMC) solutions. The Ag@ZnO-OAc nanoparticle structure and interactions between OAc and TMC were confirmed by TEM, XPS and FTIR. Surface morphology, roughness, chemical composition, hydro-philicity and charges of the synthesized membranes were characterized by SEM, FTIR, contact angle and zeta potential analyses. The results showed that incorporating the Ag@ZnO-OAc nanoparticles into the PA layer improved chemical and physical properties of the TFN membranes. Compared with the nanoparticle-free TFC membrane, the Ag@ZnO-OAc/PA TFN membrane showed a considerably higher salt rejection, and a lower flux decline rate when tested with filtration of BSA solution as a model foulant and a higher flux recovery with water flush. In addition, the Ag@ZnO-OAc/PA TFN membrane showed excellent antibacterial performance against E. Coli and S. aureus.