The luminescence and energy transfer in Pr3+–Ce3+ co-doped Lu0.8Sc0.2BO3 crystals

Lu0.8Sc0.2BO3 crystals doped with 1 at%Ce3+ and co-doped 0.1 at% and 0.5 at%Pr3+ were grown by the Czochralski method. The concentrations of Pr3+ and Ce3+ in crystals were measured by the ICP-AES method. Absorption spectra, VUV–UV spectra, fluorescence decay time and X-ray excitation luminescence spectra were investigated at room temperature. The excitation luminescence spectra of Ce3+ emission and decay curves from the lower excited state levels of the 4f15d1 and 5d1 electronic configurations of the Pr3+ and Ce3+ conspicuously indicated the non-radiative energy transfer from Pr3+ to Ce3+. The detailed pathways were shown in the energy level diagram of the respective Ce3+ and Pr3+ in Lu0.8Sc0.2BO3 host. In addition, the scintillation efficiency data indicated that the energy transfer effect is directly associated with the Pr3+ concentration.