Thin Film Nanocomposite Membranes with Tannic Acid Functionalized MXene Nanosheets for High-Performance Nanofiltration

Abstract

Nanofiltration is a membrane separation technology that efficiently separates neutral/charged solutes with little energy consumption. Reusing or treating wastewater is one of the most efficient ways to help the environment. When it comes to concentration polarization, membrane fouling, and selective permeation, however, commercial thin film composite (TFC) nanofiltration membranes exhibit more severe trade-off effects. Here, we build a TFN membrane by dispersing tannic acid (TA)-functionalized MXene (Ti3C2TX) nanosheets into the aqueous phase and incorporating them into the polyamide surface layer by interfacial polymerization. The produced membrane has been shown by a number of chemical and structural investigations to be not only porous, hydrophilic, and negatively charged but also capable of constructing transport channels in the separating layer, hence lowering the barrier to mass transfer. Changes in TA/MXene ratio and MXene nanosheet concentration allowed for fine-tuning of TMNF-TFNs membrane characteristics. Specifically, the results show that the enhanced membrane has a high water flow of 16.6 L m–2 h–1 bar–1 and a high rejection rate of divalent ions (MgSO4, Na2SO4). Important for real-world applications, the TMNF-TFN membrane also displays outstanding antifouling durability and long stability.