Composite Nanofibers for Removing Water Pollutants: Fabrication Techniques

Abstract

The world has been facing severe problems regarding air, land, and water contamination by several hazardous chemicals released in the environment, including those arising from industry activities, automobiles exhaustion, food production and consumption, and population growth. Such contaminants, including heavy metals, dyes, and emerging pollutants, can be highly hazardous for human health and terrestrial and aquatic environment. In this context, novel technologies aiming to mitigate or reduce water pollution have been sought, such as those based on filtering- and adsorption-based techniques, in which the choice and/or combination of distinct materials plays a crucial role. Polymer nanofibers have been shown to be highly suitable for such purpose, because of their attractive properties, including small diameters (at the micro- and nanoscale), large porosity, and wide surface area available for chemical functionalization. Among available fiber-forming techniques, electrospinning is capable of producing long and porous fibers of small diameters and wide surface area suitable for removing water pollutants, particularly if their surfaces are functionalized with specific chemicals, aiming at increasing adsorption capability. Solution Blow Spinning (SBS) is a more recent fiber forming technique used for producing nanofibers with properties comparable to electrospinning, but presenting several advantages such as the greatly higher output rate and no requirement of a high-voltage source, once it employs a highly pressurized dragging gas source to produce the nanofibers. Therefore, in this book chapter we will make a comprehensive text on electrospinning and solution blow spinning methods as a valuable tool to produce diverse composite micro- and nanofibers aiming at applications in water pollutants removal.