Fast UV luminescence in Pr3+-doped eulytite double phosphates

The paper presents the synthetic procedure and the structural characterisation of Pr3+-doped eulytite double phosphates Sr3La(PO4)3 and Ba3Lu(PO4)3. The luminescence properties of these materials were studied employing time-resolved VUV spectroscopy upon excitation with synchrotron radiation. The 5d–4f emission of Pr3+ ions was detected and assigned. It was shown that energy transfer from host to Pr3+ 5d states is quite inefficient. At the same time the materials demonstrate unwanted defect-related emission that presents main path for relaxation of host relaxation excitations.

► Luminescence of Pr3+ doped double eulytites Sr3La(PO4)3 and Ba3Lu(PO4)3 is examined.
► UV–VUV synchrotron radiation is applied for the time-resolved spectroscopic study.
► Pr3+ 5d-4f emission is detected and analyzed along with other emission peculiarities.
► The energy transfer from the host to the Pr3+ 5d states is found to be inefficient.
► A defect-related emission at energies lower than needed to excite Pr3+ into its d-states is the main path for relaxation of host excitations.