Characterization of boroaluminosilicate glass surface structures by B K-edge NEXAFS

Techniques traditionally used to characterize bulk glass structure (NMR, IR, etc.) have improved significantly, but none provide direct measurement of local atomic coordination of glass surface species. Here, we used Near-Edge X-ray Absorption Fine Structure (NEXAFS) as a direct measure of atomic structure at multicomponent glass surfaces. Focusing on the local chemical structure of boron, we address technique-related issues of calibration, quantification, and interactions of the beam with the material. We demonstrate that beam-induced adsorption and structural damage can occur within the timeframe of typical measurements. The technique is then applied to the study of various fracture surfaces where it is shown that adsorption and reaction of water with boroaluminosilicate glass surfaces induces structural changes in the local coordination of boron, favoring BIV species after reaction.

► Here we characterize borosilicate glass surface structure using boron NEXAFS.
► We address technique-related issues with calibration, quantification and interactions between beam and material.
► We observe beam-induced structural damage occurs within the timeframe of typical measurements.
► We observed that water adsorption and reaction at borosilicate surfaces induces structural changes in the local coordination of boron.