Carbonate coprecipitate precursors were prepared by mixed nitrate solutions containing M2+(M2+=Sr2+,Ba2+),Y3+ and Er3+ as the cation sources and(NH4)2CO3 as the precipitator.MY2S4:Er3+ phosphors were synthesized by ca...Carbonate coprecipitate precursors were prepared by mixed nitrate solutions containing M2+(M2+=Sr2+,Ba2+),Y3+ and Er3+ as the cation sources and(NH4)2CO3 as the precipitator.MY2S4:Er3+ phosphors were synthesized by calcining the carbonate precursors with CS2 as the sulfurization reagent at 1050 ℃ for 4 h.XRD patterns show that the synthesized SrY2S4 and BaY2S4 crystalline powders possess the orthorhombic [CaFe2O4]-type structure.Photoluminescent measurements indicate that there were mainly red emitting(4F9/2→4I15/2) and green emitting(2H11/2→4I15/2 and 4S3/2→4I15/2) of Er3+ in the SrY2S4 while there was only red emitting(4F9/2→4I15/2) in BaY2S4:Er3+.BaY2S4:Er3+ is considered as a novel red phosphor candidate with a high monochromaticity.展开更多
The preparation of ternary rare earth sulfides of Ln3-xEuxS4 (Ln = Ce, Pr, and Nd) ceramics was investigated, and the effect of Eu substitution on Ln3-xEuxS4 ceramics was also studied. Ln3-xEuxS4 powders were synthesi...The preparation of ternary rare earth sulfides of Ln3-xEuxS4 (Ln = Ce, Pr, and Nd) ceramics was investigated, and the effect of Eu substitution on Ln3-xEuxS4 ceramics was also studied. Ln3-xEuxS4 powders were synthesized by the sulfurization of their oxide powders using carbon disulfide gas. Ln3-xEuxS4 ceramics were sintered by pressure-less sintering method. All pressureless sintered Ln3-xEuxS4 ceramics crystallized in γ-phase. It was found that Eu substitution could improve the density of Ln3-xEuxS4 ceramics. Furthermore, Eu substitution might narrow the optical band gaps of Ln3-xEuxS4 ceramics.展开更多
文摘Carbonate coprecipitate precursors were prepared by mixed nitrate solutions containing M2+(M2+=Sr2+,Ba2+),Y3+ and Er3+ as the cation sources and(NH4)2CO3 as the precipitator.MY2S4:Er3+ phosphors were synthesized by calcining the carbonate precursors with CS2 as the sulfurization reagent at 1050 ℃ for 4 h.XRD patterns show that the synthesized SrY2S4 and BaY2S4 crystalline powders possess the orthorhombic [CaFe2O4]-type structure.Photoluminescent measurements indicate that there were mainly red emitting(4F9/2→4I15/2) and green emitting(2H11/2→4I15/2 and 4S3/2→4I15/2) of Er3+ in the SrY2S4 while there was only red emitting(4F9/2→4I15/2) in BaY2S4:Er3+.BaY2S4:Er3+ is considered as a novel red phosphor candidate with a high monochromaticity.
文摘The preparation of ternary rare earth sulfides of Ln3-xEuxS4 (Ln = Ce, Pr, and Nd) ceramics was investigated, and the effect of Eu substitution on Ln3-xEuxS4 ceramics was also studied. Ln3-xEuxS4 powders were synthesized by the sulfurization of their oxide powders using carbon disulfide gas. Ln3-xEuxS4 ceramics were sintered by pressure-less sintering method. All pressureless sintered Ln3-xEuxS4 ceramics crystallized in γ-phase. It was found that Eu substitution could improve the density of Ln3-xEuxS4 ceramics. Furthermore, Eu substitution might narrow the optical band gaps of Ln3-xEuxS4 ceramics.
