Abstract: Iron-doped TiO₂ nanoparticles were prepared via a new synthetic route.　 The photocatalytic activity was examined by the photocatalytic degradation of h eptylene.　The effects of iron dopant on the crystal structure, absorption character of light and chemical feature of the surface were studied by XRD， UV-vis and XPS techniques respectively.　The results indicate that the iron doping enlarges the absorption band of visible light of pure TiO₂, thus the efficiency of absorption of light is increased. The amount of iron dopant and the calcination temperature have a great effect on the photocatalytic activity of iron-doped TiO₂ nanoparticles.　The highest photocatalytic activity of iron-doped TiO₂ nanoparticles is the highest when the molar ratio of Fe to Ti is 0.5% and the calcination temperature is 300 ℃.

Key words: iron-doped TiO₂, nanoparticles, photocatalytic, heptylene