Development of polysulfone-nanohybrid membranes using ZnO-GO composite for enhanced antifouling and antibacterial control

Abstract

Zinc oxide nanoparticles were well-known for the enhanced antifouling and antibacterial properties which could be beneficial for membrane processes in desalination. The functionalization of ZnO onto graphene oxide nanoplates was targeted for better distribution. Both ZnO and ZnO-GO NPs were synthesized using sol-gel method. The nanoparticles characteristics were checked with XRD, TEM, and FESEM. The nanohybrid membranes were fabricated via wet phase inversion technique and embedded with various percentage of ZnO (1, 2, 3 wt%) and ZnO-GO (0.1, 0.3, 0.6 wt%) nanoparticles. All the membranes with nanoparticles incorporation exhibited improved membrane properties in comparison with the pristine PSF membrane. The best membrane performance was shown in membrane with 2 wt% of ZnO and 0.6 wt% of ZnO-GO. These two membranes presented significantly improved performance such as enhanced hydrophilicity, high permeability and porosity, improved humic acid rejection rate as well as good antifouling and antibacterial control. To an extent, the excellent antimicrobial ability of these nanohybrid membranes appeared as appropriate candidate to contribute or overcome bio-fouling issues in applications such as brackish water or seawater desalination. Hence, ZnO and ZnO-GO NPs were superb nanomaterials in the fabrication of PSF-nanohybrid membranes. The use of GO nanoplates allowed reduction of ZnO composition by up to 5 times while showing similar performances.