The preparation of tubular heterostructures based on titanium dioxide and silica nanotubes and their photocatalytic activity

Abstract

Tubular heterostructures based on titanium dioxide (TiO₂) and silica nanotubes (SNTs) with high photocatalytic activity have been successfully obtained by a simple combination of an electrospinning technique and a solvothermal process. The as-prepared products were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and N₂ absorption–desorption experiments. The results confirmed that SNTs with high specific surface area were obtained by efficiently controlling the phase separation and solvent evaporation during the process of electrospinning and calcination, and TiO₂ was successfully grown on the SNT substrates. The obtained titanium dioxide/silica nanotubes (TiO₂/SNTs) heterostructures showed high photocatalytic activities to degrade Rhodamine 6G because of the formation of heterostructures, which might improve the separation of photogenerated electrons and holes. Furthermore, the TiO₂/SNTs heterostructures could be easily recycled without an evident decrease in photocatalytic activity.