Fabrication of Superhydrophobic Polyacrylonitrile (PAN) nanofibres membranes for membrane distillation technology

Abstract

Membrane distillation (MD) is a promising water desalination technology that is capable of treating high salinity water. However, the problematic fouling issues and membrane wetting are the primary impediments to the large-scale application of this technology. To overcome the mentioned problems, the distilling membrane should be made from anti-wetting materials and possess a highly porous structure. In this study, a superhydrophobic nanofibrous membrane was fabricated through surface coating of electrospun polyacrylonitrile (PAN) nanofibres membranes using silica nanoparticles and fluorinated alkyl silane surface treatment. The coated PAN nanofibre membranes were characterised using scanning electron microscope (SEM), water contact angle (WCA) method, Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC). It was observed that the amount and size of silica nanoparticle were related to hydrolysis time, which was crucial in determining the membrane pore size and formation of superhydrophobic surface. The presence of silica nanoparticles and fluorine content significantly improved the hydrophobicity and thermal properties of the nanofibres. The results from this study provide valuable insights into the understanding of the behaviour of silica nanoparticles and the method to fabricate superhydrophobic electrospun nanofibre membranes for MD application.