CVD of TiO2 and TiO2/Ag antimicrobial layers: Deposition from the hexanuclear μ-oxo Ti(IV) complex as a precursor, and the characterization

Abstract

Hexanuclear μ-oxo titanium(IV) complex, of the general formula [Ti6O6(H2O)2(OiBu)6(O2CtBu)6], has been used as a new type of TiO2 chemical vapor deposition precursor. Thin titanium dioxide layers of a different polymorphic structure were grown on the surface of titanium foil or titanium surgical implants, as substrates, in a wide range of substrate temperatures 693–853K, under Ar atmosphere. The best antimicrobial activity revealed TiO2 covers deposited between 713 and 733K. Loose packing layers produced at 733K were doped by silver grains by CVD method using silver(I) 3,3-dimethyl tert-butyrate complex with triethylphosphane as a precursor. The increase of the antimicrobial activity of TiO2–Ag system with the increase of Ag grains content was noticed. Crystallinity, composition, and morphology of TiO2 and TiO2/Ag layers were analyzed by X-ray diffraction method, high resolution transmission electron microscopy, and scanning electron microscopy.