Color point tuning in Lu(3-x-y)Mn(x)Al(5-x)Si(x)O(12):yCe(3+) for white LEDs
Yongchao Jia1, Ning Guo, Yuhua Zheng
1State key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
Abstract:
A series of the solid-solution phosphors Lu(3-x-y)Mn(x)Al(5-x)Si(x)O(12):yCe(3+) is synthesized by solid-state reaction. The obtained phosphors possess the garnet structure and exhibit similar excitation properties as the phosphor Lu(3)Al(5)O(12):Ce(3+), but with an effectively improved red component in the emission spectrum. This can be attributed to the energy transfer from Ce(3+) to Mn(2+). Our investigation reveals that electric dipole-quadrupole interactions dominate the energy-transfer mechanism and that the critical distance determined by the spectral overlap method is about 9.21 Å. The color-tunable emissions of the Lu(3-x-y)Mn(x)Al(5-x)Si(x)O(12):yCe(3+) phosphor as a function of Mn(3)Al(2)Si(3)O(12) content are realized by continuously shifting the chromaticity coordinates from (0.354, 0.570) to (0.462, 0.494). They indicate that the obtained material may have potential application as a blue radiation-converting phosphor for white LEDs with high-quality white light.
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