Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.297, 41-48, 1997
Glassy Photochromic Layers Produced by Sol-Gel Process
Inorganic - organic composite materials on the basis of Tetraethoxysilane/3-Glycidoxypropyltrimethoxysilane containing microcrystals of AgBr, AgCl or AgBrxCl1-x were synthesized as photochromic coatings via the sol-gel route. The bonding of halide ions to components of the matrix system, such as Bromophenyltrimethoxysilane or Chloropropyltrimethoxysilane and of Ag+-ions with complexing agents such as 18-crown-6 and Aminopropyltriethoxysilane prevents the crystallization of silver halide crystals at room temperature and leads to a controlled growth of them. In the present work results of XRD- and AFM-measurements concerning crystal growth as function of the conditions of thermal treatment and UV-VIS spectroscopic investigations of the darkening and fading behaviour of the glassy coatings are shown.