Abstract This paper investigates the luminescence characteristics of Eu2+ activated Ca2SiO4, Sr2SiO4 and Ba2SiO4 phosphors. Two emission bands are assigned to the f--d transitions of Eu2+ ions doped into two different cation sites in host lattices, and show different emission colour variation caused by substituting M2+ cations for smaller cations. This behaviour is discussed in terms of two competing factors of the crystal field strength and covalence. These phosphors with maximum excitation of around 370nm can be applied as a colour-tunable phosphor for light-emitting diodes (LEDs) based on ultraviolet chip/phosphor technology.
Received: 01 December 2008
Revised: 18 December 2008
Accepted manuscript online:
Fund: Project supported by Hebei
Provincial Technology Development Foundation of China (Grant No
51215103b), and Science Foundation of Hebei
University of China (Grant No 2006Q06).
Cite this article:
Wang Zhi-Jun(王志军), Yang Zhi-Ping(杨志平), Guo Qing-Lin(郭庆林), Li Pan-Lai(李盼来), and Fu Guang-Sheng(傅广生) Luminescence characteristics of Eu2+ activated Ca2SiO4 Sr2SiO4 and Ba2SiO4 phosphorsfor white LEDs 2009 Chin. Phys. B 18 2068
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