Synthesis, optical and photocatalytic properties of mesoporous iron doped titania films
Semiconductive films based on iron doped titania are investigated to clarify the role of the doping agent content on their optical features, adsorption capability and photocatalytic properties. The titania films doped with iron ions (1-50 mol %) with highly developed mesoporous surface are synthesized by sol-gel method. The band edge shift towards visible part of the absorption spectrum becomes more pronounced with the increase in iron content pointing on the narrowing of the band gap of the semiconductor. Inhomogeneous distribution of iron atoms in the titania matrix between surface and bulk takes place as shown by EDS analysis. The formation of nanosized particles in the range of 25-50 nm is revealed by SEM images. The adsorption degree of the tetracycline hydrochloride molecules onto the film surface is strongly dependent on the film composition. Twice and thrice enhancement in the photocatalytic destruction of tetracycline hydrochloride under visible irradiation is fixed for the films containing 25 and 50 % iron ions, respectively, comparing with the pristine titania. It is proven that the photocatalytic degradation of tetracycline hydrochloride follows onto the surface of the photocatalyst.