Optical characteristics and charge transfer band excitation of Dy 3+ doped Y 2O 3 phosphor

Abstract

Dy 3+ ion-doped Y 2O 3 phosphors have been synthesized and characterized for structure and optical properties. Structural characterization reveals that the samples are well crystalline. The crystallinity and particle size increases as the sample is post annealed, while optical quenching entities are reduced due to which a significant enhancement in fluorescence is observed. The phosphor is efficiently excited by ultraviolet light and emits intense blue (486 nm), yellow (573 nm), red (666 nm), and near infrared (764 nm, 823 nm) light. The emission is also observed even if charge transfer band (CTB) is excited, via energy transfer from CTB to 4f levels of Dy 3+ ion. The intensity of yellow transition band varies with a variation in concentration of Dy 3+ ion as well as with excitation wavelength, while the intensity of other transitions remains unaffected. Thus a variation in yellow to blue color (Y/B) gives an opportunity for the development of color tunable phosphor. © 2012 Elsevier Ltd. All rights reserved.