Influence of alkali metal compound fluxes on Gd_2O_2S:Tb particle and luminescence

摘要

Gd_2O_2S:Tb phosphors with different alkali-metal compound fluxes were synthesized by molten salt method, showing high luminous intensity, monodispersity and micron size characteristics. The results indicated that from K~+ to Na~+ and to Li~+, the particles mean size tended to grow bigger. K~+ could effectively reduce the particle size without depressing the luminescence intensity. Meanwhile, after comparing the strongest emission intensity among different fluxes, it was shown that K~+ had most significance on improving the luminescence intensity. Li~+ could promote the formation of hexagonal morphology. It was also found that CO_3~(2-), PO_4~(3-) had prominent effects on optimizing particles size (at 254 nm excitation).