Preparation and Luminescence Properties of Orange-red Phosphors Ca_3Y_2(Si_3O_9)_2:Eu~(3+)

A series of orange-red phosphors Ca3Y2-2x(Si3O9)2:2xEu3+ were synthesized by a conventional solid-state reaction. Their photoluminescence properties were investigated by X-ray diffraction. The results show that the prepared Ca3Y2(Si3O9)2:Eu3+ crystals are Ca3Y2(Si3O9)2 phase. There are two excitation bands, namely, the O2–-Eu3+ intensive charge transition band(CTB) and the weak f-f transition absorption of Eu3+ in the excitation spectra. The main emissions are located at 587 and 610 nm under the excitation of 225 nm, respectively, corresponding to 5D0→7F1 and 5D0→7F2 transition, and the intensity of the former is similar to that of the latter. However, the intensive emission is located at 615 nm and the weak emission is located at 591 nm under the excitation of 392 nm. The decay time of 5D0 level in Eu3+ was determined via the time resolved spectra. The effect of Eu3+ content on the emission spectra intensity of Ca3Y2(Si3O9)2:Eu3+ was investigated. The luminescent intensity increases with increasing Eu3+ content. The concentration quenching does not occur.