Effect of incorporation of multiwalled carbon nanotubes on photodegradation efficiency of mesoporous anatase TiO₂ spheres

Composites consisting of mesoporous anatase TiO₂ spheres and multiwalled carbon nanotubes (MWCNTs) were synthesized via sol–gel and solvothermal processes. The nanocomposites showed enhanced photocatalytic activity because of their large specific surface areas (104–190 m²/g), the presence of TiO₂ in the anatase phase, and the reduced band gap energy (from 3.30 to 2.08 eV). In particular, of the materials prepared, the nanocomposite containing 20 wt% MWCNTs exhibited the best photocatalytic efficiency and degradation rate. The nanocomposites also showed improved pollutant adsorption capacity, electron–hole pair lifetime, light absorption capability, and absorbance of visible light. Further, the nanocomposites exhibited excellent stability and durability even after four cycles.