(748g) Graphene Oxide-Titanium Dioxide Nanohybrids for Designing Nanofiltration Membranes with Enhanced Permeability and Rejection in Dye Desalination

This project aims to hybridize TiO₂ onto graphene oxide (GO) nanosheets and use for preparation of loose nanofiltration membrane for dye desalination application. The effect of the functionalization time on the water flux, dye and salt rejections, and physical and chemical properties of the obtained membranes were studied. Results indicated that the TiO₂-functionalized GO membranes (F-GO) could provide very high water flux, about 4-6 times of the GO nanofiltration membrane, while keeping high dye rejection (~99% for Congo Red, Direct Red, and Evan Blue). Furthermore, F-GO membrane showed lower rejection towards Na₂SO₄ salts indicating the successful engineering of the channel size achieved by the functionalization to provide a membrane with high water flux, high dye rejection, and low salt rejection. The differences in water flux and dye rejection has been attributed to the channel size alterations by spacing created by the TiO₂ nanomaterials between layers of GO membrane.