Construction of TiO2@graphene oxide incorporated antifouling nanofiltration membrane with elevated filtration performance

Abstract

Two-dimensional (2D) graphene-based nanomaterials of atomic thickness have opened a new era for fabricating membranes with outstanding performance. In this work, a novel graphene oxide (GO) based thin film nanocomposite membrane for nanofiltration (NF) was constructed. Taking advantage of the nanochannels between graphene oxide, TiO2 nanoparticles were introduced between these GO nanosheets to form a TiO2@GO nanocomposite with dilated and stable nanochannels. The TiO2@GO incorporated membranes was prepared by interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC) monomers and embedding TiO2@GO nanocomposite in its polyamide layer. The effects of the embedded nanoparticles on the physicochemical properties of the prepared membranes, and on the NF membrane performance were investigated. The superior performance of the TiO2@GO incorporated membranes was observed in the case of 0.2wt% TiO2@GO with water flux of 22.43Lm−2h−1 at 0.4MPa and Na2SO4 rejection of 98.8%. This represents an enhancement in permeate flux by a factor 2 compared to a pristine membrane, and 5 times higher than the GO modified membrane, only with a slight compromise in the solute rejection. In addition, the introduction of the TiO2@GO endows the modified TFN membranes with an improved antifouling effect.