【作者】 刘海燕；

【导师】 杨志平；

【作者基本信息】 河北大学 ， 光学工程， 2008， 硕士

【摘要】 本文制备了几种适合近紫外光LED芯片激发的荧光粉。探索了最佳合成条件以及杂质的最佳浓度,分析了样品的晶体结构,研究了样品的发光性质。主要内容如下：(1)利用高温固相法合成了荧光粉SrZnP2O7：Tb3+,并研究了样品的发光性质。发射光谱由六个发射峰组成,分别位于420nm,442nm,492nm,545nm,584nm和620nm,对应于Tb3+的5D3→7F5,5D3→7F4,5D4→7F6,5D4→7F5,5D4→7F4和5D4→7F3的特征发射。激发光谱为从350到400nm的宽带,适合UVLED激发。研究了Tb3+掺杂浓度和电荷补偿剂Li+,Na+and K+对发光强度的影响,当Tb3+的最佳掺杂浓度是10%,电荷补偿剂为Li+时,样品的发光强度最大。SrZnP2O7：Tb3+有潜力作为适用于白光LED的绿色荧光粉。(2)利用高温固相法合成了红色荧光粉SrZnP2O7：Eu3+,并研究了样品的发光性质。样品的最强激发峰位于400nm,适合UVLED激发。在365nm激发下的发射光谱由位于591nm和597nm(5D0→7F1),616nm、624nm和629nm(5D0→7F2),656nm(5D0→7F3)及688mn(5D0→7F4)四组线状峰构成,为典型Eu3+的跃迁发射。研究了发光强度随Eu3+浓度变化情况,随着Eu3+浓度的增加未发现浓度猝灭现象,但存在猝灭趋势。并验证了Bi3+对Eu3+的敏化作用,讨论了Bi3+与Eu3+之间的能量传递。(3)利用燃烧法合成了Srln2O4：Sm3+红色荧光粉,并研究了其发光性质。发射光谱由位于红橙区的3个主要荧光发射峰组成,峰值分别位于568、606利660nm,对应了Sm3+的4G5/2→6H5/2、4G5/2→6H7/2、和4G5/2→6H9/2特征跃迁发射,其中606nm的发射最强。激发峰分别位于323、413和476nm,说明该荧光粉既可以被紫外光LED芯片激发,又可以被蓝光LED芯片激发。研究了Sm3+浓度变化对样品发光强度的影响,当Sm3+的浓度为1.5%时,样品的发光强度最大。该荧光粉由许多微小的晶粒组成,晶粒的平均直径小于500nm。更多还原

【Abstract】 In this paper, several kinds of phosphor used for ultraviolet LED were fabricated. The optimal synthesis temperature and the concentration of impurity were confirmed. The crystal structures were analyzed. The luminescence properties of samples were researched. The chief contents are given below.(1) The phosphor SrZnP2O7:Tb3+ was synthesized by the general high temperature solid-state reaction and its luminescence properties are investigated. It shows six major emission peaks locating at 420nm,442nm,492nm,545nm,584nm and 620nm, which correspond to the 5D3→7F5,5D3→7F4,5D4→7F6,5D4→7F5,5D4→7F4 and 5D4→7F3 typical transition of Tb3+, respectively. The excitation spectra contain a broad band extending from 350 to 400 nm, which is coupled well with the emission of ultraviolet light-emitting diode(UVLED). The effects of doped-Tb3+ concentration and charge compensations of Li+, Na+ and K+ on the emission intensity are also investigated. It shows that the optimum doped-Tb3+ concentration is 10% and Li+ gives the best improvement to enhance the emission intensity. The SrZnP2O7:Tb3+ is a potential green-emitting phosphor for white light emitting diode.(2) The red phosphor SrZnP2O7:Eu3+ was synthesized by high temperature solid state reaction and its luminescence properties are investigated. The strongest excitation peak of the sample is located at 400nm, which coupled well with the emission of UVLED. The emission bands peaking at 591nm and597nm (5D0→7F1),616nm、624nm and 629nm (5D0→7F2) 656nm (5D0→7F3) and 688nm (5D0→7F4), which are corresponded to the typical transition of Eu3+. The influence of the concentration of Eu+ to the emission intensity was investigated and when the concentration of Eu3+ increases, the concentration quench was not happened but the quench trend appears. It was also found that the Bi3+ in the system can increase the emission intensity of SrZnP2O7:Eu3+. The energy transfer from Bi3+ to Eu3+ in the phosphor was also discussed.(3) The red phosphor SrIn2O4:Sm3+ was synthesized by combustion and its luminescence properties were studied. The emission spectrum consists of three major orange-red emission bands. The emission peaks are located at 570 nm, 606nm and 653 nm corresponding to the 4G5/2→6H5/2、4G5/2→6H7/2、and 4G5/2→6H9/2 typical transition of Sm3+ respectively and the strongest one appears at 606 nm. Its excitation peaks appear at 323,413, 476nm which indicates that this phosphor can be excited effectively by UV and blue LED. The influences of the concentration of Sm3+ on the emission intensity were also investigated. When the concentration of Sm3+ is 6%, the strongest emission is obtained.更多还原