Single crystal and nanocrystalline Pr3+ doped LuPO4: Synthesis, structural characterization, photo- and cathodoluminescence

Single crystals and nanopowders of LuPO4 doped with 1 mol% Pr3+ have been synthesized using flux growth and coprecipitation techniques, respectively. The nanocrystalline powders have been thoroughly characterized from a structural and morphological point of view. The photoluminescence and cathodoluminescence spectra of the two materials have been measured. The spectra evidence both 5d-4f and 4f-4f emission bands located in the UV and visible regions; the relative intensities of the former are reduced in the nanopowders. This behaviour is attributed to surface quenching effects. The decay curves of the nanopowders relative to the 4f-4f transitions also appear to be affected by quenching with respect to their counterparts in the single crystal.