The effect of multiwalled carbon nanotubes and activated carbon on the morphology and photocatalytic activity of TiO2/C hybrid materials

Abstract

TiO₂ nanoparticles supported on activated carbon (AC) and multiwalled carbon nanotubes (MWCNTs) were prepared by the sol–gel method using ultrasonic irradiation. All the prepared samples were calcined at different temperatures and characterized by X-ray diffraction, nitrogen adsorption/desorption isotherms, scanning electron microscopy, transmission electron microscopy and diffuse reflectance spectroscopy. The effects of size and type of carbon on the morphology and photocatalytic activity of the resulting hybrid materials were investigated. The results showed that a decrease in the size of the carbon led to a decrease in size of TiO₂ nanoparticles. Both AC and MWCNTs retarded the transformation of anatase to rutile and also prevented the agglomeration of TiO₂ particles. The photocatalytic activity of the materials was elucidated using the photo oxidation of Acid Blue 92 under UV illumination. Chemical oxygen demand of the dye solution was measured at regular intervals and gave a good idea about the mineralization of the dye.