Enhancement of red emission intensity of Ca2Al2SiO7:Eu3+ phosphor by MoO3 doping or excess SiO2 addition for application to white LEDs

2nd International Conference on New Material and Chemical Industry

材料科学;化学工业

Jiao, H.Y.^1 ; Limao, C.R.^1 ; Chen, Q.^1 ; Wang, P.Y.^1 ; Cai, R.C.^1

College of Electric Engineering, Key Laboratory for Electronic Materials of the State Ethnic Affairs Commission of PRC, Northwest University for Nationalities, Lanzhou

730030, China^1

关键词: Emission intensity;    Excitation and emission spectra;    Intense red-emitting phosphors;    Non-stoichiometric;    Photoluminescence enhancement;    Photoluminescence intensities;    Photoluminescence properties;    Tetragonal structure;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/292/1/012058/pdf
DOI  :  10.1088/1757-899X/292/1/012058

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Ca1.86Al2(Si1-xMox)O7:0.14Eu3+and Ca1.86Al2Si1+yO7+2y:0.14 Eu3+were synthesized by solid-state reaction. X-ray powder diffraction, excitation and emission spectra were used to investigate their structures and photoluminescence properties. The results shows that the phosphor Ca1.86Al2SiO7:0.14Eu3+cannot be excited efficiently by light of 393 nm. The introduced Mo ion does not change the position of the excitation peak, but increases both the absorption at 400nm and the emission intensity of Eu3+. The intense red emitting phosphor Ca1.86Al2(Si0.95Mo0.05)O7:0.14Eu3+was obtained, which has 67% enhanced luminous intensity compared to that of the undoped sample Ca1.86Al2SiO7:0.14Eu3+. Otherwise, SiO2excess of non-stoichiometric phosphors Ca1.86Al2Si1+yO7+2y:0.14Eu3+showed the characteristic pattern of a tetragonal structure with a small SiO2concentration. The optimal phosphor of Ca1.86Al2Si1.1O7.2:0.14Eu3+has a luminous intensity about two times higher than that of the original stoichiometric phosphor Ca1.86Al2SiO7:0.14Eu3+. We confirmed that the photoluminescence intensity of the obtained phosphors is fairly enhanced by excessive SiO2. The mechanism of this photoluminescence enhancement is discussed in this paper.