A new green phosphor of SrAl2O4:Eu2+,Ce3+,Li+ for alternating current driven light-emitting diodes
Journal
Materials Research Bulletin
Journal Volume
47
Journal Issue
12
Pages
4071-4075
Date Issued
2012
Author(s)
Abstract
New phosphors are desired to overcoming the flickering luminescence of alternating current light-emitting diodes (AC-LEDs) by compensating dark duration with appropriately persistent luminescence. Here, the phosphor of SrAl 2O 4:Eu 2+,Ce 3+,Li + was developed for this application. The phosphor was synthesized with solid-state reaction method by using H 3BO 3 as flux. The XRD patterns show that the impurity phase of Sr 4Al 14O 25 which always formed together with SrAl 2O 4 during reaction was suppressed by using Ce. The charger defects caused by the non-equivalent substitution of Sr 2+ with Ce 3+ were compensated with Li +. Thus, the luminescence intensity of SrAl 2O 4:Eu 2+ was enhanced significantly by co-doping Ce 3+ and Li +. The fluorescence lifetime of the phosphor is about 36.5 ms. The energy dispersive spectra (EDS) assisted with scanning electron microscope (SEM) pictures reveal that Ce ions mainly distribute along grain boundary. © 2012 Elsevier Ltd. All rights reserved.
SDGs
Type
journal article