Bioinspired dopamine modulating graphene oxide nanocomposite membrane interposed by super-hydrophilic UiO-66 with enhanced water permeability

A composite material constructed by intercalating super-hydrophilic UiO-66 into the graphene oxide (GO) nanosheets was synthesized under the modification of polydopamine (PDA), and the PDA/RGO/UiO-66 hybrid membranes with enhanced water permeability, favorable dye separation performance and anti-fouling property were prepared on the cellulose acetate (CA) substrate by vacuum-assisted filtration method. In this work, UiO-66 nanoparticles (NPs) were introduced into the GO interlayers to inhibit their accumulation, while PDA was used to partially reduce GO and ensure the stability of the composite material. The prepared powder samples and composite membranes were subjected to PXRD, FT-IR, SEM, AFM, XPS, WCA characterizations and zeta potential tests, respectively. The results indicated that PDA/RGO/UiO-66 complex films presented more hydrophilicity with a pure water flux as high as 167.14 L/(m2·h), which increased by 256.91% compared to the PDA/RGO membrane and maintained a high dye separation performance (99.54% for MB and 87.36% for CR). Also, the improvement in surface hydrophilicity of the membrane was advantageous for heightening its fouling resistance. In general, the PDA/RGO/UiO-66 composite membranes synthesized in this paper have great potential for efficient separation and purification of dye wastewater.