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In this investigation, SiO2 /TiO2 thin films were prepared on glass and quartz glass substrates by dip coating sol-gel technique. The films were calcinated at 500 °C for 1 hour. Thickness of the films was estimated by ellipsometric measurements and it was in the range from about 30 nm to 700 nm. Refractive index of the films was also established. Chemical composition of the samples was studied by photoelectron spectroscopy. Transmittances of the samples were characterized using UV-VIS spectrophotometer. Subsequently, band gap energy (Eg) was estimated for these films. It was found that band gap energy increases with thickness of the films and their value depends on sodium diffusing from glass substrate. [ABSTRACT FROM AUTHOR]

Glassy enamels are characterized by high chemical durability. Their chemical resistance properties, however, differ from those observed for conventional oxide glasses. This is because of their specific chemical composition and microstructure determined by enamel technology. In longer periods of exploitation in corroding conditions glassy coatings deteriorate continuously, the most significant changes taking place in the near-surface region. The main goal of this work was to establish the influence of chemical corrosion on spectral properties of glassy coatings. Changes in microstructure, gloss and reflectance were studied using electron microscopy and reflectance spectroscopy. It was confirmed that enamels based on pigments have higher durability than enamels coloured by ion dyes. [ABSTRACT FROM AUTHOR]

SnO2 conducting thin films were prepared by spray pyrolysis. Glass surface was prepared by etching in HF and acetic acid solutions. Sodium barrier coatings with different compositions were prepared by the sol-gel technique. The influence of the glass surface preparation on optical properties of SnO2 was studied using reflectance spectroscopy. XPS was used as a tool to evaluate barrier properties of the coating. The morphology of the thin layer was studied by a scanning electron microscope. The results have shown that the titanium containing coating has the best sodium diffusion barrier property. The conductivity of SnO2 film strongly depends on the glass surface preparation. The lowest conductivity was measured for clean glass but the highest for alumina containing barrier coating. [ABSTRACT FROM AUTHOR]

Abstract: The results of structural studies of the glasses from Li2O–Bi2O3–PbO system were presented. Infrared spectroscopy (FTIR) and photoelectron spectroscopy (XPS) were applied to determine main structural unites and chemical composition of near-surface region. Glasses from the studied system are build up with lead in tetrahedral coordination and bismuth in octahedral coordination. Structural role of lithium relies on compensation of the electric charge and on separation of lead-reach and bismuth-reach regions preventing crystallization of the glasses. It was shown that the lithium is not present in near-surface regions. The thermal stability of the glasses was determined from DTA measurements. Optical properties in UV–vis region were also presented. [Copyright &y& Elsevier]

Abstract: Hybrid glasses based on tetraethylorthosilicate (TEOS)–trimethoxyoctylsilane (TMOS) and TEOS–tetraethylorthotitanate (TEOT)–trimethoxyoctylsilane systems were prepared by sol–gel technique. Structure of the hybrids was studied by FTIR and XPS spectroscopy. The studies reveal that the titanium is mainly in tetrahedral coordination substituting for silica and acting as a glass former. Some part of titanium is also present in octahedral coordination. Optical properties of hybrid glasses in the visible range strongly depend on amount of organic modifier and higher transparency is observed for glasses having higher content of TMOS. [Copyright &y& Elsevier]

The paper studies an influence of Ga 2 O 3 , PbO and BaF 2 on the thermal stability of tellurite glass and their properties: thermal expansion coefficient, transmittance and refractive index. Three series of gallium-tellurite glass were prepared: I – (100 − x)TeO 2 ·xGa 2 O 3 where x = 5, 10, 15 and 25 mol%, II – (85 − x)TeO 2 ·15Ga 2 O 3 ·xBaF 2 where x = 1, 3, 6, 11 mol%, III – (90 − x)TeO 2 ·10Ga 2 O 3 ·xPbO where x = 0, 5, 10 mol%. It was confirmed that stable gallium-tellurite glass can be produced without applying super-cooling methods in the range 5–15 mol% Ga 2 O 3 . Ga 2 O 3 acts only as a stabilizer of the TeO 2 glassy network when its content not exceed 15 mol%. As shown this effect is connected with the change in crystallization ability of orthorhombic and tetragonal forms of TeO 2 . It was found that the latter is preferable when Ga 2 O 3 content increases. The increase of the Ga 2 O 3 content over 20 mol% induces its spontaneous crystallization. Admixture of BaF 2 and PbO to the Te 2 O-Ga 2 O 3 glass diminishes a tendency to the glass crystallization. Tellurite glasses with Ga 2 O 3 , PbO and BaF 2 show good transmittance in the VIS, NIR and MIR up to 5.5 μm. BaF 2 and PbO, unlike Ga 2 O 3 , decrease the thermal expansion coefficient of tellurite glass. The change in the refractive index due to the admixtures was presented. [ABSTRACT FROM AUTHOR]

Abstract: Glasses of different matrix (phosphate, borate, silicate and lead-silicate) were studied for their optical properties. The effect of Er dopant on transmittance and luminescence properties was presented. The significant “red shift” and “blue shift” of UV edge absorption were discussed based on the changes in the framework of the borate and phosphate glasses, respectively. It was showed that the integral intensity of the two main optical absorption transitions monotonically increases with the order: phosphate