Iron-coated TiO2nanotubes and their photocatalytic performance

Abstract

Iron-coated TiO₂ nanotubes are successfully synthesized by treating hydrogen titanate nanotubes with Fe(OH)₃ sol. The products are characterized with transmission electron microscopy, atomic absorption spectrometer, X-ray diffraction, Raman spectroscopy, UV-visible absorption spectroscopy and nitrogen adsorption. The photocatalytic performance is evaluated by the photocatalytic degradation rates of methyl orange in aqueous solution under UV-vis light irradiation. The effects of the calcination temperature, concentration of Fe(OH)₃ sol and pH value of solution on the photocatalytic performance of iron-coated nanotubes are investigated. The results reveal that the iron-coated nanotubes exhibit better thermal stability and photocatalytic performance than their precursors. The iron-coated nanotubes can keep the nanotubular structure when calcined at 400 °C, and the specific surface area does not decrease sharply. We also discover that the pH of the solution has an obvious influence on the photocatalytic activity of iron-coated nanotubes. When the pH is about 2.4, the maximum photodegradation rate appears; moreover, the recycled catalyst still shows good photodegradation activity.