Photochemical deposition of platinum on titanium dioxide–tungsten trioxide nanocomposites: an efficient photocatalyst under visible light irradiation

Highly ordered titanium dioxide–tungsten trioxide nanotubular composites (TiO₂–WO₃) were fabricated on titanium sheets by electrochemical anodizing. Platinum nanoparticles have been successfully deposited onto TiO₂–WO₃ nanotubes by UV light photoreduction method. In this work, X-ray diffraction, field emission scanning electron microscope, ultraviolet–visible spectroscopy and energy dispersive X-ray spectrometer methods were adopted to characterize the samples. The degradation of methylene blue (MB) was used as a model reaction to evaluate the photocatalytic activity of the obtained samples. After irradiated under visible light for 60 min, the degradation rate of MB solution on unmodified TiO₂–WO₃ and Pt/TiO₂–WO₃ reached 77 and 93 %, respectively. Under the same condition, no obvious photodegradation of MB was found for bare TiO₂ (T). Kinetic research showed that photodegradation process followed the first-order reaction; the apparent reaction rate constant of Pt/TiO₂–WO₃-1 was 4.56 × 10⁻² min⁻¹ which is approximately 1.75 times higher than that on the unmodified TiO₂–WO₃. This work provides an insight into designing and synthesizing new TiO₂–WO₃ nanotubes based hybrid materials for effective visible light-activated photocatalysis.