Fabrication of porous fibers via electrospinning: strategies and applications

In this paper we review the literature on electrospinning of porous fibers of micron and nanoscale diameters. Selection of an appropriate polymer-solvent system can yield porous fibers due to phase separation, and different types of porosity are generated by different phase separation mechanisms. In comparison with porous polymeric fibers, production of porous inorganic fibers is much more complex: small molecules or atoms cannot be directly electrospun into continuous fibers and so polymer precursors are required and subsequently removed. Inorganic porous fibers can be generated based on a range of materials: carbon, silica and numerous metal oxides and mixed metal oxides. Some of the many applications of electrospun porous fibers are discussed: applications ranging from tissue engineering and drug delivery, to water treatment, sensors, photocatalysis and lithium-ion batteries.