Luminescent Properties of (SrNa)<sub>2-x </sub>Eu<sub>x</sub>(MoO<sub>4</sub>)<sub>3</sub> Red Phosphors Prepared by Using the Sol-Gel Process
- 1 Department of Applied Physics and Materials, Wuyi University, Jiangmen, China
- 2 College of Science, Guangdong Ocean University, Zhanjiang, China
- 3 Department of Applied Physics and Materials, Wuyi University, Jiangmen, China
- 4 School of Mechatronic Engineering, Wuyi University, Jiangmen, China
- 5 Department of Applied Physics and Materials, Wuyi University, Jiangmen, China
- 6 Department of Applied Physics and Materials, Wuyi University, Jiangmen, China
Abstract
A series of (SrNa) 2-x Eu x (MoO 4 ) 3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa) 2-x Eu x (MoO 4 ) 3 phosphors had an SrMoO 4 structure. The properties of these resulting phosphors have also been characterized by using photoluminescence (PL) spectra. The PL results indicate that all of the (SrNa) 2-x Eu x (MoO 4 ) 3 phosphors exhibit intense red emissions under 275, 395, and 465-nm excitation. The two strongest lines at 395 and 465 nm in the excitation spectra of these phosphors match well with the two popular emissions from near-UV and blue GaN-based light-emitting diodes. Some process parameters for Eu 3+ concentration, (C 6 H 8 O 7 ) · H 2 O concentration, and solution pH value were also investigated. For (SrNa) 2-x Eu x (MoO 4 ) 3 phosphors, there are two maximum emission intensities appearing with x = 0.6 and x = 1.4, respectively. When the molar ratio of citric acid is equal to that of metal cations and the solution pH is almost 4, (SrNa) 2-x Eu x (MoO 4 ) 3 shows the strongest emission intensity compared to those under other conditions.
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