Relative abundance of subsurface hydroxyl and molecular water species in silicate and aluminosilicate glasses

The interaction of water with glass has a profound impact on its mechanical, chemical, and kinetic properties. Water can enter the glass network either as molecular form (H2O) or hydroxyl species (OH). The resulting impact of water on glass properties depends on the relative concentrations of hydroxyl to molecular species. While attenuated total reflection infrared (ATR-IR) spectroscopy can be used to determine the presence of these species in the subsurface region of glass, there is currently no approach to characterize their relative abundance in the glass surface. In this paper, we propose a calculating method for quantifying the ratio of hydroxyl to molecular water in silicate glasses based on a combination of ATR-IR spectroscopy and secondary ion mass spectrometry (SIMS). The technique is applied to leached soda lime silicate and sodium aluminosilicate glasses under a variety of process conditions. The method presented in this paper offers a new avenue for understanding the multiple roles of water in silicate glass network structure and topology.