Stable graphene oxide-halloysite composite membrane with enhanced permeability for efficient dye desalination

[Display omitted] •Novel GO-based membrane with intercalated structure was formed by inserting A-HNTs.•A-HNTs could simultaneously improve the stability and permeability of GO membrane.•A-HNTs/GO membrane presented practical application potential in dye desalination. Owing to the excellent physical and chemical properties of graphene oxide (GO), GO-based composite membranes have emerged as efficient filters for wastewater treatment. However, less attention has been paid to GO-based composite membranes for dye desalination. Furthermore, because of the repulsive hydration force between adjacent GO nanosheets and the narrow interlayer spacing, GO-based membranes face challenges of stability and permeability. In this study, a novel GO membrane was successfully prepared via intercalation of halloysite nanotubes modified with (3-aminopropyl)triethoxysilane (A-HNTs) by vacuum filtration. The A-HNTs engineered the connection between the GO nanosheets through electrostatic interactions and chemical bonds. Simultaneously, the A-HNTs acted as spacers to enlarge the interlayer distance of the composite membranes, thus providing a continuous pathway for water and salts. The A-HNTs/GO composite membrane showed satisfactory stability and water permeability (159.40 L∙m−2∙h−1). In addition, the prepared membrane effectively separated dyes and salts (17.02% for Na2SO4, 15.24% for MgSO4, 8.86% for NaCl, 5.13% for MgCl2, 92.98% for methyl orange, 92.86% for methylene blue, 93.21% for crystal violet, and 96.32% for Congo red). Therefore, GO-based composite membranes have promising applications in the desalination of dye solutions.