Effects of Li⁺ ions on luminescent properties of Tb3+-doped silicate glasses

The Tb3+-doped silicate glasses with and without Li+ ions were synthesized by high-temperature melting method. The effects of Li+ ions on the luminescent properties of Tb3+-doped silicate glasses were studied with ultraviolet-visible transmission, emission and decay time spectra. The results show that the Li+ ion co-dopant can increase the emission intensity of Tb3+-doped silicate glasses. Additionally, the optimal Tb3+ dopant concentration can be raised from 12.8% to 15.3% in the silicate glasses with 2.0% Li+ ion co-dopant compared to those without Li+ ions. The reason is tentatively ascribed to nonbridge oxygen. The nonbridge oxygen is propitious to uniform distribution of Tb3+ ions, thereby its increase reduces the energy loss due to nonradiative transition within Tb3+ ions and increas