A novel yellowish green phosphor Tb3+ doped calcium molybdate (CaMoO4) was synthesized at 800 ℃ by conventional solid state reaction method and their crystal structure and luminescent properties were investigated. Th...A novel yellowish green phosphor Tb3+ doped calcium molybdate (CaMoO4) was synthesized at 800 ℃ by conventional solid state reaction method and their crystal structure and luminescent properties were investigated. The X-ray diffraction patterns (XRD) showed that they were simple crystalloid of CaMoO4∶Tb3+. Monitored at 550 nm, the excitation spectrum consisted of two bands and the two excitation peaks located at 305 and 380 nm respectively. The emission spectrum excited by 380 nm UV light was composed of four narrow bands. The strongest emission was located at 540 nm corresponding to 5D4-7F5 transition. The appropriate concentration of Tb3+ was 5%(mole fraction) for the highest emission intensity at 550 nm. These results showed that this Tb3+-activated CaMoO4 was a promising yellowish green phosphor for near-ultraviolet (NUV) InGaN-based white LED.展开更多
High quality Tb^3＋/Eu^3＋ co-doped cubic NaYF 4 single crystal in the size of Φ1.0 cm×6.6 cm was grown by a modified Bridgman method using KF as assistant flux for NaF-YF 3 system under the condition of complet...High quality Tb^3＋/Eu^3＋ co-doped cubic NaYF 4 single crystal in the size of Φ1.0 cm×6.6 cm was grown by a modified Bridgman method using KF as assistant flux for NaF-YF 3 system under the condition of completely closed Pt crucible.A white light emission from the combination of the violet-blue,blue,green,orange,and red lights with chromaticity coordinates of x = 0.3107,y = 0.3274,correlated color temperature of T c = 6637 K,color rendering index of R a = 83,and color quality scale of Q a = 82 could be obtained from 1.51 mol%Tb^3＋ and 1.42 mol%Eu^3＋ co-doped cubic NaYF 4 single crystal when being excited by a 369 nm light.This indicates that Tb^3＋/Eu^3＋）co-doped cubic NaYF 4 single crystal has a potential application in white light emitting diode excited by ultraviolet light.展开更多
基金the Hebei Developing Foundation of Science &Technology (51215103b)
文摘A novel yellowish green phosphor Tb3+ doped calcium molybdate (CaMoO4) was synthesized at 800 ℃ by conventional solid state reaction method and their crystal structure and luminescent properties were investigated. The X-ray diffraction patterns (XRD) showed that they were simple crystalloid of CaMoO4∶Tb3+. Monitored at 550 nm, the excitation spectrum consisted of two bands and the two excitation peaks located at 305 and 380 nm respectively. The emission spectrum excited by 380 nm UV light was composed of four narrow bands. The strongest emission was located at 540 nm corresponding to 5D4-7F5 transition. The appropriate concentration of Tb3+ was 5%(mole fraction) for the highest emission intensity at 550 nm. These results showed that this Tb3+-activated CaMoO4 was a promising yellowish green phosphor for near-ultraviolet (NUV) InGaN-based white LED.
基金supported in part by the National Natural Science Foundation of China (Grant Nos.51472125 and 51272109)K.C.Wong Magna Fund in Ningbo University
文摘High quality Tb^3＋/Eu^3＋ co-doped cubic NaYF 4 single crystal in the size of Φ1.0 cm×6.6 cm was grown by a modified Bridgman method using KF as assistant flux for NaF-YF 3 system under the condition of completely closed Pt crucible.A white light emission from the combination of the violet-blue,blue,green,orange,and red lights with chromaticity coordinates of x = 0.3107,y = 0.3274,correlated color temperature of T c = 6637 K,color rendering index of R a = 83,and color quality scale of Q a = 82 could be obtained from 1.51 mol%Tb^3＋ and 1.42 mol%Eu^3＋ co-doped cubic NaYF 4 single crystal when being excited by a 369 nm light.This indicates that Tb^3＋/Eu^3＋）co-doped cubic NaYF 4 single crystal has a potential application in white light emitting diode excited by ultraviolet light.
