Dataset: Glass-forming ability and structural features of melt-quenched and gel-derived SiO2-TiO2 glasses

Research data for Manuscript submission with title

Glass-forming ability and structural features of melt-quenched and gel-derived SiO₂-TiO₂ glasses

Abstract

SiO₂-TiO₂ glasses produced by melt-quenching or sol-gel spray-drying were compared to highlight their structural differences. Glass formation was possible by melt-quenching up to 10 mol% TiO₂, while higher contents led to devitrification. Raman spectroscopy and solid-state ¹⁷O and ²⁹Si MAS NMR confirmed the clear emergence of Ti-O-Si bonds and a tetrahedral oxygen coordination of Ti⁴⁺ leading to full network connectivity, as also substantiated by the synthesis of TiO₂-doped cristobalite. In gel-derived glasses, water content induced partial network depolymerization, thereby enhancing the solubility of TiO₂ in the hydrous silicate matrix. However, full dehydration during heating proved challenging due to the competing devitrification tendency: the glass-forming range in the anhydrous binary SiO₂-TiO₂ system does not therefore appear to be significantly enlarged by the sol-gel synthesis route.