Energy transfer process in a rare earth (Ce , Dy , Sm )-doped nanocrystalline phosphate phosphor.

This work presents the optimized luminescence spectra for the Ce ,Sm -doped NaSrPO phosphor that was synthesized using a wet chemical method. Ce and Sm are activator impurities that show spectral splitting bands that corresponds to the d-f and f-f transitions, respectively. These impurity elements shows the characteristics spectral bands when doped with the NaSrPO host lattice. Spectral splitting in the Ce excitation band was monitored in the 240-340 nm range, in which the observed bands were located at 269 nm, 292 nm and 321 nm, and emission bands were observed in the broad spectral range 330-430 nm. However, when Sm ion was doped in the same host lattice we obtained a characteristic emission band at 590 and 645 nm in the orange-red region, under sharp excitation bands located at 345, 361, 375, and 403 nm respectively. Also, we carried out energy transfer analysis in the Ce /Dy -doped NaSrPO phosphor. Further crystalline phase and the nanophase nature of the phosphor compound were confirmed using X-ray diffraction and transmission electron microscopy analyses.