Recent developments of electrospun nanofibrous materials as novel adsorbents for water treatment

Electrospun nanofibers have shown great potential for removal of contaminants from aqueous solutions owing to their large specific surface area, high porosity, easy modification, and good compatibility with other functional materials. To date, hundreds of polymers have been successfully fabricated into ultrafine nanofibers by electrospinning for adsorption purposes. In this review, the recent progress in electrospun adsorbents is summarized, and special attention is paid to the critical parameters for electrospinning of ultrafine fibers, commonly used polymers and fillers, as well as the adsorption capacities of electmspun nanocomposites for various water contaminants removal. First, various parameters including solution viscosity, polymer molecular weight, applied voltage, tip-to-collector distance, and flow rate for the fabrication of defectless and uniform nanofibers are illustrated. Electrospun fibrous adsorbents are then categorized according to their compositions, such as single polymer adsorbents, polymer composite adsorbents, and filler-added polymeric adsorbents, and their adsorption capacities towards specific contaminants are compared with discussions on the adsorption mechanism. Finally, a conclusion on recent achievements and current challenges is stated, and prospects associated with the applications of electmspun nanofibers in water treatment are provided.