Enhanced photocatalytic properties of ultra-long nanofiber synthesized from pure titanium powders

Using Ti powder as reagent, ultra-long TiO2 nanofibers were prepared via hydrothermal method in NaOH solution. The samples were characterized respectively by means of field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) with selected area electron diffraction (SAED), and X-ray diffraction (XRD). The diameter and the length of the ultra-long TiO2 nanofiber were similar to 100 nm and > 200 mu m, respectively. The ultra-long TiO2 nanofibers were anatase after heat treatment at 450 A degrees C for 1 h. Moreover, the optical properties of the products were investigated by UV-visible light absorption spectrum. Furthermore, methyl orange was used as a target molecule to estimate the photocatalytic activity of the specimens. Under the same testing conditions, the photocatalytic activity of the ultra-long TiO2 nanofibers was higher than that of P25. Direct electrical pathway and improved light-harvesting efficiency were crucial for the superior photocatalytic activity of the ultra-long TiO2 nanofibers.