Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1605452 | Journal of Alloys and Compounds | 2016 | 24 Pages |
Abstract
The physical basis of persistent luminescence in terms of the color of emission as well as the useful afterglow time is discussed for a commercial red-emitting Ca1âxSrxS:Eu phosphor. The discussion is based on the results of excitation/emission spectra and critical analysis of thermoluminescence (TL) data. The work focuses on: (i) the well known tuning of emission in Ca1âxSrxS:Eu phosphor (ii) control of intrinsic trapping parameters that decides the lifetime (Ï) of charge in traps relevant to the phenomenon of persistent luminescence. XRD data is used to characterize the commercial phosphor. The emission spectra (λex = 275 nm) reveals the prominent well known broad emission (FWHM = 0.20 eV) at 1.92 eV/647 nm of Eu2+ along with weak transitions at 1.63 eV/761 nm, 1.75 eV/710 nm, 2.13 eV/581 nm and 2.56 eV/485 nm indicating presence of europium in Eu3+ state. Rigorous analysis of TL shows that non-first order TL peaks having Ï300âmins to hours are key to persistent luminescence in Ca1âxSrxS:Eu.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
R.K. Gartia, Ngangbam Chandrasekhar,