Synthesis and photocatalytic performance of TiO₂ nanospheres–graphene nanocomposite under visible and UV light irradiation

In this article, we present a fast and simple method to produce TiO₂ nanospheres–graphene nanocomposite with high photocatalytic activity under visible and UV light irradiation. TiO₂ nanospheres were adsorbed on graphene in sol–gel process. First, titanium (IV) butoxide underwent hydrolysis in graphene oxide (GO) ethanol solution resulting in TiO₂ nanospheres deposition on GO. Next, the material was calcinated to generate the phase transition of TiO₂ into anatase and reduce GO to graphene. The detailed characterization of the material was performed via transmission electron microscopy, energy dispersive X-rays spectrometer, Fourier-transformed infrared spectroscopy, X-ray diffraction, and Raman spectroscopy. Interestingly, the band-gap energy of the prepared photocatalyst was drastically decreased in comparison with the commercial photocatalyst P25 from 3.05 to 2.36 eV. This influenced in the activation of the material under visible light and resulted in high photocatalytic activity in the process of phenol decomposition in visible and UV irradiation.