Enhancement of red emission intensity of Ca2Al2SiO7:Eu3+phosphor by MoO3 doping or excess SiO2 addition for application to white LEDs
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,SiO2 excess of non-stoichiometric phosphors Ca1.86Al2Si1+yO7+2y:0.14Eu3+showed the characteristic pattern of a tetragonal structure with a small SiO2 concentration.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.
H Y Jiao C R LiMao Q Chen P Y Wang R C Cai
College of Electric Engineering,Key Laboratory for Electronic Materials of the State Ethnic Affairs Commission of PRC,Northwest University for Nationalities,Lanzhou,Gansu,730030,PR China
国际会议
三亚
英文
1-6
2017-11-18（万方平台首次上网日期，不代表论文的发表时间）