Electrospun nanofiber affinity membranes for water treatment applications: A review

Recent environmental studies reveal that protecting freshwater resources and preventing contamination of groundwater, surface water, and seawater have become critical issues worldwide. With finite available freshwater resources on our planet, seawater desalination and wastewater treatment are the only practical options to overcome the water shortage crisis. Water reclamation using one-dimensional nanostructured materials, such as electrospun nanofibers, has recently received considerable attention. Electrospun Nanofiber Materials (ENMs) as membranes provide significantly higher flux and energy efficiency than the conventional phase inversion membranes due to their highly porous, interconnected pore structure, low transmembrane pressure requirement, while rejection of contaminants is not compromised, which makes them suitable candidates in a wide range of applications from biomedical devices to water treatment membranes. Numerous investigations have been carried out on the electrospun nanofibers' thermal, electrical, and mechanical properties prepared under various fabrication conditions. In this paper, electrospinning theories, effective synthesis parameters, and different electrospinning devices were reviewed according to the proposed potentials of the ENMs as adsorptive membranes based on past achievements and future challenges in water treatment processes. That is followed by a comprehensive discussion about ENMs' modification methods to fabricate unique ENMs architectures. Taking altogether, outlooks and conclusions are expressed in accordance with recent progress.