Enhancement of visible light photoactivity of rutile-type TiO2 by deposition of silver onto Co-TiO2/MWCNTs nanocomposite for degradation of 2,4-dichlorophenol

Abstract

Abstract In the present study, we focused on improvement of photonic efficiency of rutile-type TiO2 by cobalt doping, various amounts of silver deposition and decorating on multi walled carbon nanotubes (MWCNTs) (AgCoTC samples). X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM), diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM) and nitrogen physisorption were used to characterize the synthesized samples. The XRD outcomes showed the existence of AgCl NPs in the prepared samples. The photonic efficiency of the sample was examined via photodegradation of 2,4-dichlorophenol (2,4-DCP) solution exposed to visible light. In the existence of pure TiO2 and AgCoTC photocatalyst, 2,4-DCP was degraded by 27% and 60% under visible light following180 min irradiation, respectively. The good visible light activity of AgCoTC sample can be related to the effect of the surface plasmon resonance of Ag/AgCl, and the presence of cobalt and MWCNTs can increase the photonic efficiency and change surface properties to reach sensitivity to visible light. The active species trapping experiment showed that the OH• radicals and h+ are key active species in photocatalytic reaction. Finally, reusing the optimal photocatalyst (AgCoTC(2.0)) did not result in any decline of its catalyst performance for degrading 2,4-DCP under visible light after three cycles.