Li_2CO_3/K_3PO_4复合助熔剂对新型Y_2O_2S:0.09Ti长余辉磷光体发光性能的影响  

Influence of Li_2CO_3/K_3PO_4 Flux Ratio on the Luminescent Properties of Y_2O_2S ∶Ti Phosphor

作　　者：张朋越[1] 向鑫[1] 沈华翔[1] 潘毓[1] 洪樟连[1] 王民权[1] 

机构地区：[1]浙江大学材料科学与工程系

出　　处：《发光学报》2006年第2期169-173,共5页Chinese Journal of Luminescence

基　　金：教育部留学回国人员科研启动基金(SRFforROCS;SEM;2003-14);浙江省教育厅(20030265)资助项目

摘　　要：采用高温还原法合成了一种新型无稀土掺杂Y2O2S：0．09Ti长余辉发光材料。基于助熔剂种类对长余辉发光材料特性的重要作用，选择了对余辉衰减初期和后期余辉强度有明显作用的Li2CO3和K3PO4两种助熔剂，研究了不同配比（以下用x表示，x=Li2CO3／（Li2CO3＋K3PO4））的复合助熔剂对Y2OS：0．09Ti磷光体晶体结构和发光性能的作用，以获得具有较好综合发光性能的Y2O2S：0．09Ti磷光体。采用PL光谱和余辉测试仪对材料的发光特性进行了表征，用XRD研究了其晶体结构的变化。XRD结果表明，在复合助熔剂范围内（x=0-1．0）均可获得单相性的Y2O2S：0．09Ti磷光体。同时发现复合助熔剂比例不同制备的样品中，Y2O2S：0．09Ti磷光体晶体择优取向也发生明显的变化，且高比例Li2CO3有助于Y2O2S：0．09Ti磷光体的晶体形成。复合助熔剂比例x对样品的激发峰与发射谱主峰位置（565nm）基本没有影响；但助熔剂比例x对发射峰强度则有明显影响，随着x增加，该磷光体的发光强度先增后减，在x=0．8时发光强度最大。As the added flux has much more severe effect on the luminescence properties, the influence of Li2CO3/（Li2CO3 -4-K3PO4 ） flux ratio x （x = Li2CO3/（ Li2CO3 ＋ K3PO4 ）） on the luminescence properties of Y2O2S：0.09Ti phosphor has been investigated to obtain the best luminescence and afterglow intensity. The composite flux of Li2CO3 plus K3PO4 was selected because Li2CO3 and K3PO4 flux have been demonstrated in previous study to improve the afterglow intensity in the beginning stage and long time stage, respectively. PL spectra and afterglow measurement were used to analyze the effect of flux ratio on the luminescence and afterglow properties of Y2O2S： 0.09Ti phosphor. And XRD measurements were carried out to verify the crystal structure. XRD results showed that the single phase Y2O2S ： 0.09Ti phosphor could be obtained when flux ratio x increases from 0 to 1.0, while the grain growth orientation may change obviously. The fact that excitation spectra are similar in all flux range demonstrates that the flux ratio has little effect on the excitation process. Nevertheless, the emission spectra showed that the intensity of emission peak at 565 nm depended greatly on the flux ratio. Luminescence intensity of Y2O2S ： Ti phosphor increased with an increase of Li2CO3 ratio x, then reduced as x over 0.8. On the other hand, afterglow brightness of Y2O2S ： Ti was enhanced at appreciate Li2CO3/ （Li2CO3 ＋K3PO4） ratio of about 0.4 with an enhanced afterglow brightness（9.1 mcd · m^-2） at decay time of 30 min. This value is about four times as that of single Li2CO3 doping（2.4 mcd · m^-2）, and two times as that of single K3PO4 doping （4.3 mcd · m^-2）. Above results about the effect of flux ratio on luminescence after glow properties could be used to adjust the overall properties of Y2O2S ： 0. 09Ti phosphor. The best afterglow with yellow color is obtained at appreciate Li2CO3/ （Li2CO3 ＋ K3PO4 ） ratio of about 0.4, and its afterglow can last over 5 h with recognizable intensity

关 键 词：复合助熔剂 无稀土掺杂 Y2O2S:Ti 发光 长余辉材料 

分 类 号：O482.31[理学—固体物理]