Photocatalytic Activity for Hydrogen Evolution of Electrospun TiO₂ Nanofibers

Abstract

We report herein a simple procedure for the fabrication of TiO₂ nanofibers by the combination of electrospinning and sol−gel techniques by using poly(vinylpyrrolidone) (PVP), titanium(IV) butoxide, and acetylacetone in methanol as a spinning solution. TiO₂ nanofibers (260−355 nm in diameter), with a bundle of nanofibrils (20−25 nm in diameters) aligned in the fiber direction, or particle-linked structures were obtained from the calcination of as-spun TiO₂/PVP composite fibers at temperatures ranging from 300 to 700 °C. These nanofibers were utilized as photocatalysts for hydrogen evolution. The nanofiber photocatalyst calcined at 450 °C showed the highest activity among the TiO₂ nanofibers tested such as ones prepared by the hydrothermal method and anatase nanoparticles (Ishihara ST-01). These results indicate that one-dimensional electrospun nanofibers with highly aligned bundled nanofibrils are beneficial for enhancement of the crystallinity, large surface area, and higher photocatalytic activity.