Cathodoluminescence and photoluminescence of nanocrystal phosphors

Nanocrystals of Tb- or Eu-doped ZnS were prepared using a new technique yielding high luminescent efficiency. The photoluminescent intensities of nanocrystal ZnS:Tb and ZnS:Eu were about three times higher than those of bulk phosphors. These nanocrystals were coated by a glass ingredient. The cathodoluminescent efficiency was improved by contriving the synthesis of glass-ingredient-coated nanocrystals. The cathodoluminescent intensities of the nanocrystals were more than ten times higher than those of uncoated nanocrystals. While the composition of uncoated nanocrystal phosphor changed by electron bombardment, the glass-ingredient-coated nanocrystal phosphor was protected from surface oxidation. Glass ingredient plays a role in the reduction of phosphor degradation by bombardment of electron-beams. (C) 2002 The Electrochemical Society.