Thin Film Nanocomposite\nMembranes with Tannic Acid\nFunctionalized MXene Nanosheets for High-Performance Nanofiltration

Abstract

Nanofiltration is a membrane separation technology that\nefficiently\nseparates neutral/charged solutes with little energy consumption.\nReusing or treating wastewater is one of the most efficient ways to\nhelp the environment. When it comes to concentration polarization,\nmembrane fouling, and selective permeation, however, commercial thin\nfilm composite (TFC) nanofiltration membranes exhibit more severe\ntrade-off effects. Here, we build a TFN membrane by dispersing tannic\nacid (TA)-functionalized MXene (Ti₃C₂T_X) nanosheets into the aqueous phase and incorporating them into the\npolyamide surface layer by interfacial polymerization. The produced\nmembrane has been shown by a number of chemical and structural investigations\nto be not only porous, hydrophilic, and negatively charged but also\ncapable of constructing transport channels in the separating layer,\nhence lowering the barrier to mass transfer. Changes in TA/MXene\nratio and MXene nanosheet concentration allowed for fine-tuning of\nTMNF-TFNs membrane characteristics. Specifically, the results show\nthat the enhanced membrane has a high water flow of 16.6 L m^–2 h^–1 bar^–1 and a high rejection\nrate of divalent ions (MgSO₄, Na₂SO₄). Important for real-world applications, the TMNF-TFN membrane also\ndisplays outstanding antifouling durability and long stability.