Enhancement of Photocatalytic Activity on TiO₂-Nitrogen-Doped Carbon Nanotubes Nanocomposites

Abstract

TiO 2 -nitrogen-doped carbon nanotubes (TiO 2 -CNx) nanocomposites are successfully synthesized via a facile hydrothermal method. The prepared photocatalysts were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric and differential scanning calorimetry analyses (TGA-DSC). The results show that the TiO 2 nanoparticles with a narrow size of 7 nm are uniformly deposited on CNx. The photocatalytic activity of the nanocomposite was studied using methyl orange (MO) as a model organic pollutant. The experimental results revealed that the strong linkage between the CNx and TiO 2 played a significant role in improving photocatalytic activity. However, the mechanical process for CNx and TiO 2 mixtures showed lower activity than neat TiO 2 . Moreover, TiO 2 -CNx nanocomposites exhibit much higher photocatalytic activity than that of neat TiO 2 and TiO 2 -CNTs nanocomposites. The improved photodegradation performances are attributed to the suppressed recombination of electrons and holes caused by the effective transfer of photogenerated electrons from TiO 2 to CNx.