Carbon nanotubes/TiO2 nanotubes composite photocatalysts for efficient degradation of methyl orange dye

A series of carbon nanotubes/TiO2 nanotubes (CNTs/TNTs) composite photocatalysts were successfully prepared by incorporation of CNTs in HNO3 washing process. These photocatalysts were characterized by XRD, N2 physical adsorption, UV–vis diffuse reflectance spectroscopy, TEM and Raman spectroscopy, respectively, and their photocatalytic activities were tested by using methy1 orange (MO) as a model compound. Also, the effects of amount of CNTs incorporated, calcination temperature and amount of catalyst on the photocatalytic activity of the composite photocatalyst were systematically investigated. The results show that the CNTs/TNTs composite exhibits much higher photocatalytic activity than that of the TNTs or CNTs alone.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► CNTs/TNTs composite photocatalysts were prepared by mixing CNTs and TNTs in nitric acid solution. ► Photocatalytic activities were evaluated under UV light using methyl orange as model pollutant. ► CNTs/TNTs with CNTs content of 0.10 calcined at 450 °C exhibited higher photocatalytic activity. ► Degradation efficiency of CNTs/TNTs was reduced only 7.6% after three cycles for methyl orange.