Incorporating MXene@MOF-303 Composites into Poly(vinyl alcohol) (PVA) to Fabricate Pervaporation Membranes for Desalination

MXene has a multilayer structure, which can be peeled and layered into single or multilayer nanosheets, and it possesses multiple functional groups that can be easily modified. MOF-303, a kind of metal–organic framework material, was synthesized by the solvent hydrothermal method using aluminum ion as the center metal and 3,5-pyrazole dicarboxylic acid as the organic ligand. In this paper, MOF-303 was grown in situ on Ti3C2Tx MXene to synthesize the MXene@MOF-303 composite, which combined the advantages of both MXene and MOF-303. Using the MXene@MOF-303 composite as blending fillers and a polyacrylonitrile (PAN) ultrafiltration (UF) membrane as the substrate, an MXene@MOF-303/poly(vinyl alcohol) (PVA)/PAN composite membrane was fabricated. The composites and membranes were characterized by FTIR, XRD, SEM, and the pervaporation desalination of the composite membrane was also tested. The experimental results showed that the incorporation of MXene@MOF-303 composites improved the separation performance of the PVA membrane. The MXene@MOF-303/PVA/PAN composite membrane, loaded with 0.5 wt % of MXene@MOF-303, achieved a high flux of 15.87 kg·m–2·h–1 and a rejection of 99.84% when desalinating 3.5 wt % NaCl solution at 35 °C by pervaporation.