The red-emitting phosphors of Eu{sup 3+}-activated MR{sub 2}(MoO{sub 4}){sub 4} (M = Ba, Sr, Ca; R = La{sup 3+}, Gd{sup 3+}, Y{sup 3+}) for light emitting diodes
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China)
- Faculty of Engineering, Kyoto Sangyo University, Kamigamo, Kyoto 603-8555 (Japan)
Graphical abstract: The luminescence quantum efficiencies of Eu{sup 3+}-doped MY{sub 2−x}Eu{sub x}(MoO{sub 4}){sub 4} show the dependence on the Eu{sup 3+} doping (x) for M = Ca (a), Sr (b), Ba (c). Display Omitted Highlights: ► Eu{sup 3+}-activated MY{sub 2}(MoO{sub 4}){sub 4} (M = Ba, Sr, Ca) were firstly prepared. ► Comprehensive investigations of QEs and thermal stabilities of Eu{sup 3+}-activated MR{sub 2}(MoO{sub 4}){sub 4} (M = Ba, Sr, Ca; R = La, Gd). ► BaYEu(MoO{sub 4}){sub 4}, SrY0.6Eu1.4(MoO{sub 4}){sub 4} and CaEu{sub 2}(MoO{sub 4}){sub 4} are the best choice for solid state lighting because of high QEs and thermal stabilities. -- Abstract: A series of red-emitting phosphors of MR{sub 2}(MoO{sub 4}){sub 4}:Eu{sup 3+} (M = Ba, Sr, Ca; R = La{sup 3+}, Gd{sup 3+}, Y{sup 3+}) were prepared by solid-state reaction. The photoluminescence excitation and emission spectra were investigated. The phosphors can be efficiently excited by the near UV light and exhibit a red luminescence corresponding to the electric dipole transition {sup 5}D{sub 0} → {sup 7}F{sub 2} at 615 nm. The optimum doping in MY{sub 2−x}Eu{sub x}(MoO{sub 4}){sub 4} (M = Ba, Sr, Ca) were investigated by the dependence of luminescence quantum efficiency (QE) on the Eu{sup 3+} concentrations. The absolute luminescence quantum efficiencies were measured for all the samples. The luminescence thermal satiability was checked by measuring the temperature-dependent luminescence intensities in temperature region of 10–450 K. The results indicate that the three phosphors of BaYEu(MoO{sub 4}){sub 4}, SrY{sub 0.6}Eu{sub 1.4}(MoO{sub 4}){sub 4} and CaEu{sub 2}(MoO{sub 4}){sub 4} are the best choice for white-LEDs to be used for lighting. This was evaluated in details by taking into account of the properties such as the excitation spectra, the luminescence QEs, the red color coordinates, the luminescence quenching of Eu{sup 3+}-doping concentrations and the thermal stability.
- OSTI ID:
- 22215699
- Journal Information:
- Materials Research Bulletin, Vol. 47, Issue 12; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
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