Efficient energy transfer mediated by intrinsic SiO2 nanocrystals in Eu+3-doped lead borosilicate glasses

► SiO2-B2O3-PbO2 glass doped with different Eu3+ ion concentrations was analyzed. ► High Eu3+ ions concentration inhibit SiO2 crystallization process in the SBP glass. ► Non-bridging oxygen hole center and OH groups stabilized on the SiO2 NC surface. ► Efficient energy transfer from intrinsic NC surface enhances the ion luminescence.