In this works, rare earth ion doped core and core-shell Y2O3 phosphors have been extensively studied for many
applications due to the high stability and emission range and intensity. The core-shell Y2O3: (RE= Eu, Dy, Tb)
nanoparticles are synthesized using a two-step process in which 100-150 nm Y2O3 core particles are synthesized using a
molten salt synthesis and the shell is deposited using a sol-gel process The core-shell architecture was designed for
enhanced luminescence efficiency with long emission lifetimes. Specifically, a multi-shell architecture was necessary to
spatially separate Dy3+, Eu3+ and Tb3+ within the phosphor to circumvent the energy transfer to the surface quenching
sites. First, the crystallinity of Y2O3nanophosphors was characterized using X-ray analysis. RE-doped Y2O3 core
nanoparticles have a good compositional homogeneity. We have also recorded emission spectra and measured
fluorescence lifetime. After coating passive shell layer, emission spectra and measured emission lifetimes were
compared with those form Y2O3 nanophosphor core system and the effectiveness of these core-shell phosphors were
successfully assessed.
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