Synthesization and luminescent properties of blue emitting phosphor Ba2Ca(PO4)2：Eu2+

A blue emitting phosphor Ba2Ca(PO4)2:Eu2+ is synthesized by a high temperature solid state method. Effect of the conditions is inverstigated, such as preparation temperature and time, the ratio of Ba/Ca, and Eu2+ concentration, on the phase and luminescent property. Results show that Ba2Ca(PO4)2 and Ba2Ca(PO4)2:Eu2+ have been achieved by selecting the appropriate conditions, such as the temperature 900/1200 ℃ and the time 4 h. The compound Ba2Ca(PO4)2:Eu2+ produces an asymmetric emission band centered at 454 nm under 343 nm UV excitation. For the 454 nm emission, the excitation spectrum extends from 200 to 450 nm with a peak at 343 nm, and has an obvious excitation band in the range of 350–410 nm. With increasing Eu2+ concentration, there occur the concentration quenching effect and redshift phenomenon. With decreasing ratio of Ba/Ca, there has an obvious enhancement in the green region, and the emission color gradually turns from blue to cyan. It is shown that the Eu2+ ion not only can occupy the Ba2+ site but also the Ca2+ site. Therefore, different luminescence centers of Eu2+ can exist in Ba2Ca(PO4)2, and affect its luminescence.