Developing an antibacterial super-hydrophilic barrier between bacteria and membranes to mitigate the severe impacts of biofouling

Biofouling produces concentrated microbial populations with highly resistive biofilms and is considered to be a serious obstacle for a wide range of membrane technology applications. An antibacterial super-hydrophilic barrier could help to reduce biofouling by preventing direct contact between membranes and bacteria. In this study, an antibacterial super-hydrophilic barrier consisting of a layer of TiO2 nanoparticles (NPs) was developed on polyvinylidene fluoride (PVDF)-based membrane via a facile technique. The results demonstrated that the presence of TiO2 NPs eliminated the first step of biofouling, ie bacterial adhesion to the membrane. In addition, after bacterial deposition onto the membrane during ultrafiltration (UF), the TiO2 NPs significantly retarded bacterial growth and reproduction (the second step of biofouling). During UF, the membrane flux decreased due to bacterial deposition, but 85% of the flux was recovered through physical cleaning using water. This study sheds light on the potential advantages of antibacterial super-hydrophilic membranes for biofouling mitigation.