Synthesis and luminescence properties of Ce3+-doped RbBaPO4

A novel Ce3+ doped RbBaPO4 phosphor was prepared via the conventional solid state reaction. The phosphor was investigated by XRD, photoluminescence excitation and emission spectra. This phosphor exhibited an emission peak in the range of 345-355 nm under 303 nm excitation. Four 5d levels corresponding to the 4f-5d transition of Ce3+ were identified. The spectroscopic parameters, for example, the 5d barycenter, crystal field splitting and stokes shift were discussed. The optimal Ce3+ concentration and its critical energy transfer distance were determined to be 9 mol% and about 13 Å respectively. The corresponding concentration quenching mechanism was deemed to be the electric dipole-quadrupole interaction. The spontaneous emission probability of the transition between the excited state (5d) and the ground state (2FJ(J=7/2,5/2)) was discussed quantitatively. Significantly, the configurational coordinate diagram was firstly engaged to illustrate the red shift phenomenon, indicating a distinctive approach for depicting the red shift.