The luminescent properties of Eu^3+doped Ca2SiO4 red phosphors synthesized by the flux fusion reaction method were investigated. It was found that the excitation spectrum included two regions: the weak excitation ba...The luminescent properties of Eu^3+doped Ca2SiO4 red phosphors synthesized by the flux fusion reaction method were investigated. It was found that the excitation spectrum included two regions: the weak excitation band below 325 nm and strong narrow peaks above 325 nm. The main peak of the excitation band was located at 400 nm. The peaks located at 290 nm were assigned to the combination of the charge transfer transition of O-Eu, peaks above 325 nm (325, 385, 400, 470, 511, and 539 nm) were assigned to the f-f transitions of Eu^3+. The emission spectrum was dominated by the red peak located at 612 nm due to the electric dipole transition of ^5D0-^7F2. In addition, the effects of the Eu^3+ content and charge compensators of Li^+, Na^+, K^+, and Cl^- ions on the emission intensity were investigated. The experiment results suggested that the strongest emission was obtained when the concentration of the Eu^3+ ions was 0.3 mol^-1, and Li^+ ions gave the best improvement to enhance the emission intensity. Ca2SiO4:Eu^3+, Li^+ was thus suitable for low-cost trichromatic white light emitting diodes (WLED) based on UV InGaN chip.展开更多
基金supported by Jiangxi Provincial Department of Education (GJJ08344)
文摘The luminescent properties of Eu^3+doped Ca2SiO4 red phosphors synthesized by the flux fusion reaction method were investigated. It was found that the excitation spectrum included two regions: the weak excitation band below 325 nm and strong narrow peaks above 325 nm. The main peak of the excitation band was located at 400 nm. The peaks located at 290 nm were assigned to the combination of the charge transfer transition of O-Eu, peaks above 325 nm (325, 385, 400, 470, 511, and 539 nm) were assigned to the f-f transitions of Eu^3+. The emission spectrum was dominated by the red peak located at 612 nm due to the electric dipole transition of ^5D0-^7F2. In addition, the effects of the Eu^3+ content and charge compensators of Li^+, Na^+, K^+, and Cl^- ions on the emission intensity were investigated. The experiment results suggested that the strongest emission was obtained when the concentration of the Eu^3+ ions was 0.3 mol^-1, and Li^+ ions gave the best improvement to enhance the emission intensity. Ca2SiO4:Eu^3+, Li^+ was thus suitable for low-cost trichromatic white light emitting diodes (WLED) based on UV InGaN chip.