Thermal evolution of Fe2O3-TiO2 sol-gel thin films

Fe₂O₃-TiO₂ thin films were deposited on silica glass slides using three sol-gel solutions containing Ti-butoxide and different iron oxide precursors. The thermal evolution of the coatings was followed by DTA-TGA and XRD from 200 to 1000°C. All the iron-containing samples were amorphous up to 700°C, when a phase separation between iron and titanium oxides was evidenced by the presence of crystalline Fe₂O₃. Above that temperature a titanate compound (pseudobrookite) formed according to the equilibrium phase diagram. The use of different precursors did not affect the thermal evolution and all the different samples exhibited the same trend.