Vol. 44, Issue 2, pp. 337-344 (2014)
Keywords
silica porous glass, photochromic high silica glass, transmission electron microscopy (TEM), X-ray diffraction (XRD), UV–VIS–IR transmission spectra
Abstract
The structure of photochromic high silica glasses (PHSGs) was studied by UV–VIS–NIR and IR spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. PHSG plates were obtained by impregnation of silica porous glasses at first with AgNO3 aqueous solution (in or without the presence of the sensitizers, such as Cu(NO3)2 or Ce(NO3)3), next in the mixed halide salt (NH4Cl, KBr, KI) solution. Then a part of the samples was sintered at temperatures from 850 to 900 °C up to closing of the pores. The results of TEM study have shown that the PHSG plates have two-phase structure with inclusions of the size of 10–100 nm. According to XRD data, the PHSGs contain the AgBr phase. IR spectra confirmed the presence of AgI, AgCl, CeO2, CuCl2, CuCl phases in PHSGs.