Fabrication of a novel and green thin-film composite membrane containing nanovoids for water purification.

Abstract Thin film nanocomposite (TFN) membranes, which incorporate nanomaterials in a crosslinked polyamide matrix, often show enhanced separation properties thanks to the additional pores or channels offered by these materials. In this study, we deliberately created nanovoids in the dense polyamide rejection layer by acid-etching copper nanoparticles (CuNPs) contained in a TFN membrane. Systematic membrane characterization confirmed the complete removal of CuNPs using 1% HNO 3 , which formed nanovoids of approximately 10 nm in size. The water flux of the etched membrane TFC-Cu50X was nearly quadrupled compared to that of the CuNPs loaded membrane TFC-Cu50. This significantly improved water flux can be ascribed to the enhanced water transport through these nano-sized voids. The nanovoids-enhanced approach provides new possibilities for synthesizing high performance membranes. Graphical abstract fx1 Highlights • A nanovoids-enhanced TFC membrane was prepared. • Systematic characterization results confirmed the complete removal of CuNPs. • The nanovoids containing TFC membrane achieved 4-fold water flux than that of CuNPs loaded membrane. • The nanovoids-enhanced TFC membrane showed linear relationship between water flux and applied pressure. [ABSTRACT FROM AUTHOR]