In this work, the polyamide (PA) membrane surface has been modified by coating of nanomaterials including graphene oxide (GO) and titanium dioxide (TiO2) to enhance membrane separation and antifouling properties. The influence of surface modification conditions on membrane characteristics has been investigated and compared with a base membrane. Membrane surface properties were determined through scanning electron microscope (SEM) images and Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy. Membrane separation performance was determined through the possibility for the removal of methylene blue (MB) in water. Membrane antifouling property was evaluated by the maintained flux ratios (%) after 120 minutes of filtration. The experimental results showed that the appearance of hydrophilic groups after coating of GO and TiO2 nanocomposite materials with or without UV irradiation onto membrane surface made an improvement in the separation property of the coated membranes. The membrane flux increased from 28% to 61%; meanwhile, the antifouling property of the coated membranes was improved clearly, especially for UV-irradiated PA/GO-TiO2 membrane.

In this study, the polyamide thin film composite membrane surface has been modified by anti-microbial silver nanoparticles (AgNPs). The membrane surfaces were interwoven with AgNPs by ultraviolet grafting polymerization method using AgNPs with or without poly(ethylene glycol) (PEG). The membrane surface characteristics were determined by scanning electron microscopy-energy dispersive x-ray spectrometry images, attenuated total reflection-Fourier transforms infrared spectroscopy, water contact angle values, and anti-bacterial property. The separation performance was determined based on the flux and the ability to remove calcium ions in water. The anti-biofouling property was appraised through the maintained flux ratios and the irreversible fouling factors of unmodified and modified membranes during 10 h-filtration of protein bovine serum albumin (BSA) in an aqueous solution, in which, before filtration of BSA, all membranes were immersed in E. coli bacteria solution for 4 days. The results of the experiments corroborated the hydrophilicity and more anti-microbial property of the membrane surfaces after being incorporated into AgNPs. The water contact angle decreased from around 49 for the unmodified membrane to 36 and 23 for the AgNPmodified membranes without/with PEG, while no colonies appeared in the medium containing the AgNP-modified membranes. The separation property of modified membranes was improved, with both membrane flux and antifouling properties, along with the substantial surge of the anti-biofouling property. After 10 h of BSA filtration, the fluxes of the modified membranes were maintained at 68% and 78% for AgNP-modified membranes without and with PEG, respectively. Conversely, this value was only 46% for the unmodified one.

This study endeavors to augment the antibacterial and anti‐biofouling properties of thin‐film composite polyamide membranes by subjecting them to modification with antibacterial chitosan and silver nanoparticle materials through the UV‐induced graft polymerization technique. Various surface assessment methods were employed, and the efficiency of the membrane performance was demonstrated through the flux and the retention of the filtration process, which used calcium chloride as the foulant. Antibacterial, antifouling, and anti‐biofouling capabilities were assessed through several tests. The findings revealed that the chitosan/silver nanoparticles‐grafted membranes exhibited superior antibacterial and anti‐biofouling abilities with consistent flux and enhanced retention, underscoring the prospective implementation of this approach in filtration systems to curtail biofouling and bolster overall efficacy.