Ultraviolet-radiation-induced structure and long-lasting phosphorescence in Sn2þ—Cu2þco-doped silicate glass

We report the relaxation of ultraviolet-radiation-induced structure and long-lasting phosphorescence in Sn2þ—Cu2þ co-doped glass with composition of 70SiO2.20Na2O·10CaO·0.05CuO·0.05SnO in mol ration. After irradiation by an ultraviolet lamp λmax ¼ 254 nmÞ with a power density if 5 mW/cm2 for 30 min, a visible light peaking at 510 nm could be observed with the naked eyes in the dark after the removal of the activating light. Thermostimulated luminescence glow curves and electron-spin-resonance spectra were measured. We suggest that the long-lasting phosphorescence in the Sn2þ—Cu2þ co-doped glass samples resulted from the recombination of electrons and holes at shallow traps in the glass matrix that can be thermally released at room temperature.