Preparation and photoelectrocatalytic properties of titania/carbon nanotube composite films

Composite films of TiO₂ and carbon nanotubes (CNTs) were prepared on titanium sheets by liquid phase deposition and the photoelectrocatalytic (PEC) properties of the films were investigated through the degradation of methyl orange (MO) in 0.1 M solutions. It was demonstrated that CNTs in the TiO₂ film significantly decreased the charge transfer resistance and increased the anodic photocurrent response of the film under UV light irradiation when the bias was above −0.1 V. The PEC performance of the CNT-based composite film could be tuned by controlling the preparation parameters including the deposition time and calcination temperature. The deposition time and calcination temperature were optimized at 1 h and 450 °C, respectively. On the TiO₂/CNT film prepared under the optimized conditions, 95% of the added MO (10 mg L⁻¹) was degraded within 90 min, which was much higher than the 60% removal seen on the pure TiO₂ films.