Comparative study of photo-induced variations of X-ray diffraction and refractive index in photo-thermo-refractive glass

Recovery of high surface area mesoporous silica from waste hexafluorosilicic acid (H2SiF6) of fertilizer industry

“…5 shows the X-ray diffraction pattern for recovered sodium fluoride from hexafluorosilicic acid. The three prominent sharp peaks located at 20, 39, and 56 • matches with the expected NaF standard XRD peaks [17]. No other crystalline phases detectable by XRD were found indicating the purity of NaF, as also substantiated through EDS study (Figs.…”

Effect of cooling on the optical properties and crystallization of UV-exposed photo-thermo-refractive glass

“…Glasses which undergo photo-thermo induced crystallization were invented many years ago by Stookey [1] and have been studied as possible candidates for hologram writing in the last 15 years [2][3][4][5]. PTR glass exhibits significant refractive index change after UV-exposure and thermal treatments (pre-nucleation + development) above the glass transition temperature, T g , which results from the crystallization of about 0.1 wt% sodium fluoride nanocrystals [6]. After partial crystallization the glass remains highly transparent in the visible.…”

“…The evolution of the crystallization and optical properties of PTR glass after UV-exposure is reported in several publications [6,[10][11][12][13][14], and described in reviews, e.g. [15].…”

Silica materials recovered from photonic industrial waste powder: Its extraction, modification, characterization and application

“…The residual SiO 2 could be due to insufficient NaOH amounts applied in the extraction process. The major component of NaF presented in the sediment was also demonstrated by [18,19]. Besides, there was a broad peak centering at 22 • as observed from Fig.…”