Effect of composition and phase separation on structure and luminescence properties of Tb3+ doped borosilicate glasses

Two borosilicate glass series with different Na2O/B2O3 ratio and different phase separation probability have been doped with largely different concentrations of Tb3+. The addition of rare earth elements increases the phase separation tendency of borosilicate glasses, allowing to study the process in detail. Phase separation structures were also modified by annealing the glass samples at different temperatures and times. The occurring effects were studied by high resolution transmission electron microscopy (TEM) as well as with static and dynamic luminescence measurements. Strong effects of glass composition, doping concentration, and annealing on the intensity and shape of the luminescence spectra and the time-resolved luminescence are found and explained.