Novel method for doping nano TiO₂photocatalysts by chemical vapour deposition

Highly active photocatalytic Fe-doped nano TiO2 was successfully synthesised by chemical vapour deposition (CVD) method using FeCl3 as Fe source. CVD was carried out by evaporating FeCl3 at 350°C in nitrogen flow during 30–90 min. The amount of Fe incorporated into TiO2 framework is adjusted by the amount of FeCl3 used and the evaporation time. The obtained sample was characterised by X-ray diffraction (XRD), atomic absorption spectroscopy (AAS), energy dispersive X-ray spectroscopy (EDS), UV-Vis, Fourier transform-infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). Photocatalytic activities of the samples were tested in photocatalytic decomposition of 2-propanol in liquid phase using visible light instead of UV light irradiation. Non-doped TiO2 and high Fe loading TiO2 samples showed very low photocatalytic activity, whereas the low Fe loading TiO2 sample exhibited high photocatalytic activity under visible light. The high photocatalytic activity of this sample was rationalised by the existence of defects (Ti–OH groups) as the active sites.