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Fe 2 O 3 -TiO 2 coatings were successfully prepared on glass slide substrates using sol-gel method for photocatalytic applications. The phase structure, thermal, microstructure and surface properties of the coatings were extensively characterized by using X-ray diffractometry (XRD), differential thermal analysis/thermograviometry (DTA/TG), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Their adhesion and absorbance properties were investigated by a scratch tester and UV-vis spectroscopy. Four different solutions were prepared by changing Fe/Ti molar ratios. Glass substrates were coated by solutions of Ti-alkoxide, Fe-chloride, glaciel acetic acid and isopropanol. The obtained gel films were dried at 300 • C for 10 min and subsequently heat-treated at 500 • C for 5 min in air. The oxide thin films were annealed at 600 • C for 60 min in air. The influence of Fe 3+ concentration and number of layers on structure of the films was established. In addition, XRD results revealed that Fe 2 O 3 -TiO 2 films composed of TiO 2 , Fe 2 Ti 3 O 9 , Ti 3 O 5 and Fe 3 O 4 phases. According to DTA/TG result, it was determined that endothermic and exothermic reactions were formed at temperatures between 80 and 650 • C due to solvent removal, combustion of carbon based materials and oxidation of Fe and Ti. SEM observations exhibited that the coating structure becomes more homogeneous depending on an increase of Fe/Ti molar ratios and thus a regular surface morphology forms with increasing Fe/Ti ratio. It was also seen that as the Fe/Ti ratio increases the surface roughness of the films increases. Critical adhesion force of thin films with Fe/Ti ratio of 0, 0.07, 0.18 and 0.73 were found to be 9, 25, 28 and 21 mN, respectively. The methylene blue solutions photocatalyzed by TiO 2 based thin films shows characteristic absorption bands at 420 nm.

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In this paper, Ni-TiO2 nanocomposite coatings with different sizes of TiO2 nanoparticles were successfully prepared by electrodeposition process from a nickel electrolyte in which the TiO2 nanoparticles were suspended. The influence of relevant deposition parameters on the nanocomposite coating characteristics was discussed. X-ray diffractometer has been applied in order to investigate the phase structure of the nanocomposite coatings. The surface morphology of nanocomposite coatings was characterized by a scanning electron microscopy equipped with an energy dispersive spectroscopy. The electrodeposited nanocomposite coatings obtained at different deposition parameters were evaluated for their mechanical and corrosive properties. Obtained results show that the size of TiO2 nanoparticles and applied current density during deposition process has a direct effect on mechanical and corrosive properties of nanocomposite coatings. Increasing current density and smaller nanoparticle size has affirmative effect on mechanical properties, whereas corrosion resistance of nanocomposite coatings deposited at 3 A dm −2 current density are higher than the coatings prepared at higher current density values.