Facile synthesis of AC@TiO2-S with improved visible light photocatalytic activity and recyclability through a controllable sol–gel approach

A photocatalyst (AC@TiO2-S) based on active carbon (AC) as a support and TiO2 as active sites has been successfully prepared through a facile, controlled sol–gel approach and characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), nitrogen adsorption analysis, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Importantly, the as prepared AC@TiO2-S exhibits much higher photocatalytic activity than the catalyst AC@TiO2-G (prepared by sol–gel approach) for the degradation of methyl orange (MO) under visible light irradiation (λ > 420 nm). Additionally, this supported catalyst can be easily separated from the reaction system and reused for up to five cycles without significant loss in activity, indicating its excellent recyclability. On the basis of the results, AC@TiO2-S is promising for application in the degradation of other dyes, and the controllable sol–gel method can be applied in other fields.