The aim of the present work was to establish the influence of the Fe-dopant on the structure and photocatalytic properties of the sol-gel TiO2 nanopowders. The relationship between the synthesis conditions and the properties of titania nanosized materials, such as thermal stability, phase composition, crystallinity, morphology and size of particles was investigated. Undoped, 0.5, 1, 2 and 5 wt% Fe-doped TiO2 samples have been prepared and structurally characterized by the XRD method. Lattice parameters, crystallite sizes, internal strains, as a measure of structural disorder, were determined. X-ray photoelectron spectroscopy (XPS) and magnetic measurements completed the structural data study. The acceptance of the dopant by the titania lattice was proved by the XRD measurements and the positive values of the magnetic susceptibilities. Its addition is responsible for supplementary defects in the crystalline lattice (paramagnetic behaviour). The dopant was present in the low spin state (LS) of Fe3+ in the sample with 0.5 wt% iron concentration and in the high spin state (HS) in the other samples. It influenced the photocatalytic properties. The photocatalytic activity of the prepared nanopowders has been tested in the degradation of nitrobenzene from water, as a first mention in literature. The sample with 0.5 wt% Fe dopant concentration thermally treated at 400 degrees C presented the best photocatalytic activity. (C) 2014 Elsevier B.V. All rights reserved.