Investigations on the optical and mechanical properties of organic dye metal oxide composite films

Organic-inorganic composite films consisting of different dye pigments and metal oxide matrices with various concentration ratios have been prepared by mixed evaporation. The surface morphology, optical and mechanical properties have been investigated by means of atomic force microscopy, ex-situ and in-situ optical spectroscopy (UV-VIS, color measurements) and nanoindentation measurements. It is shown that color collection can be essentially enlarged using different dye pigments and embedding simultaneously several dye pigments into the inorganic matrices, respectively. The film hardness is mainly limited by pigment concentration and the kind of matrix material. Using dye-ZrO2 composites with small dye contents (10-30 vol%), film hardness up to about 6 GPa is obtained. Additional practical testing methods have been applied to study the corrosion resistance, and the light and temperature stability of dye and composite coatings. The investigations reveal a higher light sensitivity of composites in comparison with pure dye films. (C) 1997 Elsevier Science S.A.