da Silva, Alison Abreu [UNESP]Cebim, Marco Aurelio [UNESP]Davolos, Marian Rosaly [UNESP]2014-05-202014-05-202008-07-01Journal of Luminescence. Amsterdam: Elsevier B.V., v. 128, n. 7, p. 1165-1168, 2008.0022-2313http://hdl.handle.net/11449/26018Gadolinium oxysulfide powders doped with different Tb3+ concentrations were prepared from sulfur vaporization on rare earths' basic carbonate precursors. Single-phase Gd2O2S samples were obtained, with Tb3+ doping up to 9 at%. The study of the excitation mechanisms revealed that the Tb3+ emission might occur after the direct Tb3+ excitation either by energy transfer from Gd3+ or from the phosphor host. The characteristic terbium emission lines were observed, resulting from the radiative decay from D-5(3) or D-5(4), to F-7(j) levels. The cross-relaxation phenomenon was observed and its effects on the materials emission color were discussed based on the CIE diagram. By using time-resolved spectroscopy, D-5(3) -> F-7(J) and D-5(4) -> F-7(J) transitions were separated. (c) 2007 Elsevier B.V. All rights reserved.1165-1168engscintillatorluminescencecross relaxationemission tuningArtigo10.1016/j.jlumin.2007.11.095WOS:000255568900011Acesso restrito42848093425462872034352556339501