Chromaticity Dependence on Eu Concentration in Y₂O₃:Eu Nanopowder

F.A.Hessari¹, Y.Ganjkhanlou¹, M.Kazemzad¹

f_a_hessari@yahoo.com, yadolah1@gmail.com, kazemzad@gmail.com

1-MATERIALS AND ENERGY RESEARCH CENTER; P. O.  BOX: 31787- 316

Abstract

Y₂O₃:Eu has been considered as an important phosphors compound having better chemical and thermal stability than sulfur¨Cbased phosphors. However, its unfavorable chromaticity diminishes the substitution of sulfur based phosphors by this material. In this work, Y₂O₃:Eu nanopowders were synthesized by urea combustion method containing different concentration of Eu. The synthesized Y₂O₃:Eu nanopowders were characterized by X-ray diffractometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction, energy dispersive X-ray analysis (EDX), FT-IR and photoluminescence spectroscopy. The particle size was calculated to be in the range of 10 -30 nm using Scherrer?¯s formula. The Ia-3 structure of synthesized Y₂O₃:Eu nanopowders was confirmed with X-ray diffractometry. The crystallinity of Y₂O₃:Eu nanopowders was confirmed by SAED and TEM images. The ⁵D₀¨C??⁷F_J (J=0, 1, 2, 3,) and ⁵D₁¨C⁷F₁ transitions bands were observed at 575-650 and 530-550 ranges in the photoluminescence spectrum. The quenching concentrations for ⁵D₂??⁷F₀ and ⁵D₂??⁷F₁ transition bands were 5 and 3 mol % of Eu resptively. The best chromaticity to the standard red color was observed with the sample containing 3 mol % Eu.

Keyword: chromaticity, Y₂O₃:Eu, photoluminescence, Nano-size, quenching concentrations