A water-resistant precursor in a wet process for TiO2 thin film formation

Abstract

Deposition of anatase TiO₂ thin films on soda-lime glass has been achieved by firing an adhered precursor titanium(IV) complex of ethylenediamine-N,N,N′,N′-tetraacetic acid (H₄edta) between 450 and 550 °C in air. The coating solution was prepared by the reaction of a neutral [Ti(H₂O)(edta)] complex, obtained from TiCl₃ and H₄edta in an air-oxidation process, with dipropylamine in ethanol. The crystal structures of the oxide films on glass substrates were examined by XRD, and some of their optical properties and electronic structure were investigated by XPS. It was shown that TiO₂ film formation was attainable employing a water-resistant precursor derived from a stable metal complex. The thermal properties of the initial [Ti(H₂O)(edta)] complex and the facile preparation of the precursor ethanol solution are also reported.