Photocatalytic degradation of formaldehyde by nanostructured TiO2 composite films

Abstract

Interest in the photocatalytic oxidation of formaldehyde from contaminated wastewater is growing rapidly. The photocatalytic activity of the nanocrystalline Fe3+/F− co-doped TiO2–SiO2 composite film for the degradation of formaldehyde solution under visible light was discussed in this study. The films were characterised by field emission scanning electron microscopy (FE-SEM) equipped with energy-dispersive spectroscopy, X-ray diffraction (XRD), BET surface area, UV–Vis absorption spectroscopy, and photoluminescence spectroscopy. The FE-SEM results revealed that the Fe3+/F− co-doped TiO2–SiO2 film was composed of uniform round-like nanoparticles or aggregates with the size range of 5–10 nm. The XRD results indicated that only the anatase phase was observed in the film. Compared with a pure TiO2 film and a singly modified TiO2 film, the Fe3+/F− co-doped TiO2–SiO2 composite film showed the best photocatalytic properties due to its strong visible light adsorption and diminished electrons-holes recombination.