Mussel-inspired modification of 2D MoS2 to construct a hybrid nanocomposite membrane with enhanced pervaporation dehydration of isopropanol

Abstract

In this work, a thin-film nanocomposite (TFN) membrane was constructed using a hybrid polydopamine (PD)-MoS2 (MoS2@PD) filler for pervaporation dehydration of isopropanol. The exfoliated MoS2 was first modified through bio-inspired coating of PD. The resulting MoS2@PD with different weight ratio with respect to PEI was then deposited into the hydrolyzed polyacrylonitrile support through pressure-assisted filtration, followed by crosslinking with trimesoyl chloride. Characterization experiments were performed with the membranes using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy, X-Ray Photoelectron Spectroscopy, Energy-Dispersive X-ray Spectroscopy, Field Emission Scanning Electron Microscopy, Atomic Force Microscopy, and water contact angle analyses. The PD serves as a bridging agent between MoS2 and the crosslinked PEI, enhancing the membrane’s physicochemical properties, including surface morphology and hydrophilicity. For membrane performance on pervaporation dehydration of 70/30 wt% isopropanol/water mixture at 25 °C, the addition of MoS2@PD led to a simultaneous increase in permeation total flux and water content in the permeate. Notably, MoS2@PD0.3-TFN membrane demonstrated a permeation flux of 2870.10 g∙m−2∙h−1 and 0.86/99.14 wt% isopropanol/water permeate mixture. The membrane also maintained stable performance under varying feed concentration, feed temperature, and long-term operations. This study contributes valuable insights into the development of MoS2-based membrane with enhanced pervaporation separation performance.