Doped nanocrystalline phosphors for low voltage displays

Recent discovery of efficient doped nanocrystalline (DNC) luminescent materials in the size range of 30 - 50 E can yield low voltage phosphors for Field Emission displays (FED). The surface related nonradiative contribution in the nanocrystalline phosphors can be reduced by the incorporation of the activator. In this work we report the variation of luminescent efficiency with size of doped nanocrystalline Y₂O₃:Tb phosphor. A correlation between the optical and microstructural properties of the samples was established. The microstructural properties of the doped nanocrystals were studied using transmission electron microscopy (TEM). The sizes as determined from electron microscopy, were correlated with the luminescent efficiencies of the doped nanocrystalline phosphors. We observe that the decrease in the particle size of the doped nanocrystalline phosphor results in the increase of the photoluminescent efficiency. This result indicates that the surfaces do not play a dominant role in the efficiency in the doped nanocrystalline phosphors and should allow us to produce better low voltage displays