SOL-GEL PROCESSING OF TITANIUM-CONTAINING THIN COATINGS .2. XPS STUDIES

Through X-ray photoelectron spectroscopy, chemical composition and the valency state of elements modified by SnO2, Fe2O3 and SiO2 titanium-based coatings has been studied. It has been established that metal alkoxides and salts used as precursors after a certain thermal treatment of the layer are transformed into the respective oxide stable state. At depth in the coatings, oxides of Ti(IV) and Sn(IV) are unstable and exhibit stoichiometrical disturbances. The phenomenon is discussed in relation to argon-ion sputtering conditions, the inhibition of the diffusion of sodium ions from the glass substrate, and the residual carbon from organic radicals. It has been proved that sol-gel processing, using (C4H9O)4 Ti as precursor, may be successfully applied for the synthesis of good, highly reflective oxide coatings of compositions, correlating with those of the starting sol solution.