Mutual influences of sol-gel matrices and dopants on the materials optical properties
Wybrane pełne teksty z tego czasopisma
The optical properties of doped sol-gel derived materials were studied. Two types of materials were examined; thin films doped with titanium dioxide and bulks doped with pH indicators: Bromothymol Blue and Nile Red. Different amounts of TiO/sub 2/ (in concentrations: 20, 40, 60 and 80 mol%) were entrapped into the silica sol-gel thin films. The refractive indices of the films were measured. A linear increase of refractive index with increasing addition of TiO/sub 2/ was observed. Bromothymol Blue and Nile Red pH indicators were entrapped into the sol-gel bulks. Two methods of dye immobilization were used. In the first method, indicators were mixed with liquid hydrolyzate used for bulk preparation. In the second one, the dried sol-gel bulks were impregnated with liquid dye solutions. The absorption spectra in the visible range were examined for dyes in solutions and sol-gel bulks. Changes in absorption spectra were observed depending on the way of dopant entrapment.
bibliogr. 11 poz.