DIRECT DEPOSITION OF MESOSCOPICALLY ASSEMBLED DYE-DOPED SILICA FILMS FROM AQUEOUS-SOLUTIONS OF SILICON ALKOXIDES

Silica films incorporating organic dyes, such as Rhodamine B and Dispe rse Red 1, were directly deposited on a substrate from aqueous solutio ns of phenyltriethoxysilane (PhTES). The organic dyes were homogeneous ly dispersed and firmly trapped in a silica matrix. The X-ray diffract ion patterns indicated that the dye-doped films have a mesoscopically assembled structure. Since the period of the mesostructure, ca. 12 Ang strom, was almost the same as the average distance between the dye mol ecules, the dye-doped films were suggested to be formed by assembling micelle-like clusters consisting of a monomer of the organic dyes surr ounded with the hydrolyzed silica precursors. Thus, the monomers of th e dyes were tightly captured in a three-dimensional cage of the silica network. Mesoscopically porous silica films were obtained by calcinat ion of the deposited films.