Heterostructured TiO2/WO3 Nanocomposites for Photocatalytic Degradation of Toluene under Visible Light

Abstract

Toluene, as a strong carcinogen, is widely found in the newly renovated rooms, shopping malls, and workshops. Photocatalytic oxidation has great superiority and application prospects for the degradation of toluene. However, low photocatalytic efficiency under visible-light irradiation arising from easy agglomeration of the solid catalysts hinders their photodegradation of toluene gas. In this work, heterostructured TiO2/WO3 photocatalysts were fabricated via an electrospinning technology combining the hydrothermal treatment. The special microstructure and composition allowed the photogenerated electrons quickly transfer from the TiO2 nanofibers to the WO3 nanorods, and thus effectively reduced the recombination of photogenerated electrons and holes. Coupling TiO2 with the narrow band-gap WO3 broadened the spectral response range of TiO2. The heterostructured TiO2/WO3 photocatalysts exhibited a remarkably higher degradation rate of toluene gas than that of the bare TiO2 nanofibers under visible-light irradiation. The photocatalysts were deposited onto the inner walls of the photoreactor and some nylon meshes. The meshes were also placed in the photoreactor in a direction perpendicular to the air flow. The meshes increased the contact between photocatalysts in solid phase and toluene in gas phase, and about 85.3% of the toluene had been degraded in the experimental conditions.