Luminescence properties and charge compensation of Sr3Al2O6 doped with Ce3+ and alkali metal ions

Sr3Al2O6:Ce3+ phosphors were synthesized by a solid-state reaction method under mild reducing atmosphere of activated carbon. The effects of H3BO3 flux on the luminescence intensity and the optimum concentration of Ce3+ for luminescence property have been investigated. The effect of a small amount of charge compensators like Li+, Na+, K+ and Rb+ on Sr3Al2O6:Ce3+ phosphor has also been studied. Sr3Al2O6:Ce3+, R+(R = Li, Na, K and Rb) exhibit superior blue emission around 460 nm to Sr3Al2O6:Ce3+ and can be effectively excited by 395 nm light, which implies that efficient charge compensation can promote the luminescence of Ce3+ in Sr3Al2O6. The Sr3Al2O6:Ce3+, R+ (R = Li, Na, K and Rb) have potential application as a blue phosphor for n-UV chip excited white LEDs.