Surface Dissolution and Diffusion of Oxygen Molecules in SiO2 Glass

Surface dissolution and diffusion of oxygen molecules (O2) in SiO2 glass were studied by their photoluminescence at 1272 nm excited with a titanium sapphire laser oscillating at 765 nm. The dissolution of O2 from ambient atmosphere at both surfaces was much faster than the following diffusion of O2 into SiO2 glass, indicating that the surface dissolution is not the rate-limiting step for the saturation of SiO2 glass with O2. The time- and temperature-dependent concentration changes of O2 allow to evaluate the diffusion coefficient and the saturation solubility of O2 in SiO2 glass.