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Nanocomposites of metal oxides are useful materials for operation in many energy conversion systems. In this study, such nanocomposites were prepared by oxidation of mixtures of iron and titanium precursor metallic thin films at 520 °C under air atmosphere. The metallic films with different iron percentages were obtained by radio frequency (RF) magnetron sputtering on glass and silicon substrates. The films were characterized by means of X-Ray Diffraction (XRD), Raman spectroscopy, UV-vis spectroscopy, High Resolution Scanning Transmission Electron Microscopy (HRSTEM), Ellipsometry and X-ray Photo-electron Spectroscopy (XPS). The results show that these films present mainly two nanometric phases, namely Fe2O3 and TiO2. A phase separation was observed; the film surface was found to be iron rich oxide or clusters of iron rich oxide (Fe x O y , x > y), whereas titanium accumulated deeply in the bulk, forming TiO 2 far below the film surface. A red shift of optical absorption as well as a relatively stable high refractive index (varying between 3.1 and 3.5) over a broad band of optical frequencies was observed for the films containing higher iron initial concentrations.

Anatase TiO2nanobelts supported on Ti sheet and decorated by hematite Fe2O3nanocrystals were prepared by an easy-to-achieve three-step soft chemistry route and evaluated for its visible-light photocatalytic performances.

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A variety of chemical and physical procedures could be used for synthesis of silver nanoparticles. However, these methods are confronted with many problems including use of toxic solvents. A green method for silver nanoparticles synthesis using dittrichia viscosa leaves extract is proposed. This plant is available in abundance on the coastal Mediterranean countries can replace polyvinylpyrrolidone conventionally used in the synthesis of silver nanoparticles. Polyol method (reflux heating) was used for silver nanoparticles synthesis. The nanoparticles obtained were characterised using X-ray diffraction, ultraviolet-visible spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and transmission electron microscopy. Compared with silver nanoparticles prepared by polyvinylpyrrolidone and ethanol 96%, the bactericidal effect of silver nanoparticles synthesised by dittrichia viscosa is more efficient against bacteria. No toxic solvents were used in the present work; therefore, it is an environmentally safe method with potential for biomedical applications.

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