Electrospun Nanofibers for Air Filtration

With rapid urbanization and industrialization, both worsening particle pollution and rising living standards have contributed to the urgent need for novel, high-performance, and energy saving media for air filtration. The effective promotion of air filters proposed for fibrous materials requires small fiber diameter, small pore size, and optimized packing structures. Electrospinning, as an advanced nanotechnology for processing polymeric nanofibers, has gained wide attention by virtue of its capacity for large-scale production of nanofibers with controlled structures from various materials. And, electrospun nanofibers show the integrated features of small diameter, small pore size, high porosity, and controllable stacking structures, which make them promising candidates for effective air filtration. In this chapter, the structural and performance advantages of and filtration mechanisms for nanofibers are summarized to present a brief introduction to electrospun nanofiber filters. Then, we review the current development of electrospun-nanofiber-based air filters, which can be divided by the type of nanofiber material, including polymeric nanofibers, hybrid nanofibers, nanofibers/nets, and inorganic nanofibers, and discuss their structural properties and filtration performance systematically. We believe that electrospun nanofibers can be used directly or incorporated into window screening, respirators, and air purifiers to diminish the negative impact of air pollution in various air filtration applications.