Fabrication of Titania Nanofibers by Electrospinning

This paper describes a procedure based on electrospinning for generating nanofibers of anatase with controllable diameters and porous structures. When an ethanol solution containing both poly(vinyl pyrrolidone) (PVP, Mw ≈ 1 300 000) and titanium tetraisopropoxide was injected through a needle under a strong electrical field, composite nanofibers made of PVP and amorphous TiO2 were formed (with lengths up to several centimeters) as a result of electrostatic jetting. These nanofibers could be subsequently converted into anatase without changing their morphology via calcination in air at 500 °C. The average diameter of these ceramic nanofibers could be controlled in the range from 20 to 200 nm by varying a number of parameters such as the ratio between PVP and titanium tetraisopropoxide, their concentrations in the alcohol solution, the strength of the electric field, and the feeding rate of the precursor solution. Both supported and free-standing mats consisting of anatase nanofibers have been successfully fabricated.