High-energy electron irradiation and B coordination in Na2O–B2O3–SiO2 glass

The effects of high-energy electron irradiation and the fractions of B atoms in particular sites in a Na borosilicate glass have been studied using time resolved electron energy loss spectroscopy in a scanning transmission electron microscope. Conversion of B atoms from the tetrahedral into trigonal coordination under irradiation has been observed. A mechanism for high-energy electron irradiation processes in Na borosilicate glasses is proposed based on the evolution of the near-edge fine structures of the B K, Si L and O K-edges.