Synergistic effect of MIL-88A/g-C3N4 and MoS2 to construct a self-cleaning multifunctional electrospun membrane

Abstract A double-layer [MIL-88A/graphitic carbon nitride(g-C3N4) + MoS2] nanofiber was prepared by electrospinning technology as a functional layer for fabricating a multifunctional hydrophilicity filter membrane (named as C-P@MIL-P@MoS2) after coating a smooth and dense chitosan (CS) on the nanofiber surface. This C-P@MIL-P@MoS2 membrane exhibted excellent adsorption and oxidation performance for eliminating dyes and Sb(III) in printing and dyeing wastewater. When adding H2O2 and light conditions at the same time, the C-P@MIL-P@MoS2 membrane can completely degrade 50 mg·L−1 of MB within 20 min. Further mechanism research found that the PAN(polyacrylonitrile)@MIL-88A/g-C3N4 catalytic layer and PSF(polysulfone)@MoS2 promoter layer have a good synergistic effect, which can produce more hydroxyl radicals(·OH) for effectively degrading MB. The pure water flux can reach 431.2 LMH when the C-P@MIL-P@MoS2 membrane is used as the filter membrane, while [MB+Sb(III)] wastewater flux is significantly influenced by the membrane fouling. The photo-Fenton reaction on [MIL-88A/g-C3N4 + MoS2] layer can efficiently degrade MB by ·OH to recover the water flux of contaminated membrane and increase the rejection rate. Meanwhile, Sb(III) was oxidized to Sb(V) with low toxicity and adsorbed on MIL-88A/g-C3N4 particles in the C-P@MIL-P@MoS2 membrane for removal. In this study, the MoS2 co-catalyst was introduced into the multifunctional catalytic membrane for the first time, which provide a new idea for the development of high-efficiency self-cleaning filter membranes.