Electronic structure and luminescent properties of Ca₅(PO₄)₂(SiO₄):Eu²⁺ green-emitting phosphor for white light emitting diodes

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• 作者：Hua Yu^a ; ^{yuhua5101@163.com} ; Degang Deng^b ; Yinqun Li^b ; Shiqing Xu^b ; ^{sxucjlu@hotmail.com} ; Yinyan Li^b ; ^c ; Cuiping Yu^a ; Yanyan Ding^a ; Hongwei Lu^a ; Haoyong Yin^a ; QiuLin Nie^a
• 关键词：Ca5(PO4)2(SiO4) ; Eu2+ ; Phosphors ; Luminescence ; White LEDs
• 刊名：Optics Communications
• 出版年：2013
• 出版时间：15 February, 2013
• 年：2013
• 卷：289
• 期：Complete
• 页码：103-108
• 全文大小：1091 K

文摘

A green-emitting phosphor, Eu²⁺-activated Ca₅(PO₄)₂(SiO₄) phosphor was synthesized by conventional solid-state reaction. X-ray powder diffraction (XRD) and FT-IR spectra analysis confirmed the phase formation. The calculated band structure shows that Ca₅(PO₄)₂(SiO₄) is an insulator with a band gap ¡Ö4.98 eV, which is close to the experimental value ¡Ö5.16 eV from the diffuse reflection spectrum. The photoluminescence excitation and emission spectra, the concentration dependence of the emission intensity and decay curves of the phosphor were investigated. The results showed that Ca₅(PO₄)₂(SiO₄):Eu²⁺ could be efficiently excited by UV chips (360-400 nm) and Eu²⁺ has three emission centers in Ca₅(PO₄)₂(SiO₄). The nature of the Eu²⁺ emission in Ca₅(PO₄)₂(SiO₄), e.g. the major mechanism for concentration quenching were discussed in order to further investigate the potential application for white light-emitting diodes (LED).