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1.
采用高温固相法在氢气还原气氛下制备了光致发光材料SrAl2O4:Eu^2+,Dy^3+。研究助熔剂用量、焙烧温度、保温时间等因素对材料发光性能的影响。研究表明助熔剂用量、焙烧温度、保温时间对材料的发光性能影响很大,且均存在一个最佳值,当基质原料中助熔剂用量为15%(质量分数),焙烧温度为1250℃,保温时间为4h时所得发光材料的性能最好。XRD测试表明,所制备的材料SrAl2O4:Eu^2+,Dy^3+属单斜晶系;发射光谱测试表明,材料SrAl2O4:Eu^2+,Dy^3+的发光光谱是以Eu^2+为发光中心位于525nm的带状谱。  相似文献   

2.
采用高温固相反应法,在还原气氛下制备了掺稀土离子Eu^2 和Dy^3 的铝酸锶长余辉光致发光材料。XRD研究表明,所制备的铝酸盐具备SrAl2O4的晶体结构。SrAl2O4:Eu^2 ,Dy^3 发光材料的发光光谱是中心位于520nm的带状谱,激发峰波长范围位于300nm~500nm,发光余辉可持续12h以上。研究了SrAl2O4:Eu^2 ,Dy^3 发光材料的耐温性和耐水性,结果表明,随热处理温度升高,发光亮度下降;水浸使发光材料与水反应生成水化物,使发光性能下降。  相似文献   

3.
基质组成对xSrO·yAl2O3∶Eu2+,Dy3+发光性能的影响   总被引:2,自引:0,他引:2  
研究了基质组成对xSrO·yAl2O3∶Eu2+,Dy3+体系长余辉发光性能的影响,并对其影响机理进行了探讨.XRD分析和长余辉发光性能表明:改变Al2O3/SrO比率可以获得长余辉发光性能较好的3种基质相:SrAl2O4∶Eu2+,Dy3+和Sr4Al14O25∶Eu2+,Dy3+及SrAl4O7∶Eu2+,Dy3+.激发与发射光谱性能分析和余辉衰减特性分析结果表明:随着基质中Sr/Al比例的减小,激发光谱向短波方向延伸,发射峰蓝移,初始余辉亮度越高,余辉持续时间越长.热释光谱分析表明:贫锶相晶格中的陷阱深度与密度较大,因而显示出较好的长余辉发光性能.  相似文献   

4.
采用高温固相法在氢氩混合气中还原制备光致发光材料Sr4Al14O25∶Eu^2+,Dy^3+。用XRD研究Sr4Al14O25∶Eu^2+,Dy^3+的结构;用荧光光度计研究助熔剂用量、焙烧温度、恒温时间等因素对材料发光性能的影响;用稳态/寿命荧光光谱议研究发光材料的余辉衰减特征。结果表明,助熔剂用量、焙烧温度、恒温时间对材料的发光性能影响很大,且均存在一个最佳值。当基质原料中助熔剂用量为15%(质量),焙烧温度为1300℃,保温时间为6 h时,制得的材料发光性能最好,初始亮度达7000 cd/m^2,余辉时间达15 h。XRD测试表明所制备的Sr4Al14O25∶Eu^2+,Dy^3+材料属正交晶系,余辉衰减服从I=At-n规律。  相似文献   

5.
利用复合有低压紫外汞灯、抽真空高纯石英玻璃管的高低温试验箱模拟空间环境中的远紫外辐照条件,对可用于航天器示踪研究的SrAl2O2O4:Eu^2+,Dy^3+发光材料进行了空间环境中的紫外稳定性考核试验,并检测比较了材料在考核前后发光性能、物相组成、粉体表面形貌及粒度的变化。结果表明:在考核前后材料的物相组成未发生改变,但粉体颗粒间发生了团聚且表面结晶程度受到一定的破坏,导致材料的发光强度有一定的衰减。但相对于硫化物系长余辉发光材料,SrAl204:Eu^2+,Dy^3+是一种空间环境中紫外稳定性较好的发光材料。  相似文献   

6.
Bright long afterglow phosphorescence glasses were prepared by using SrAl2O4: Eu^2+, Dy^3+ phosphors and suitable glass frits together. The SrAl2O4: Eu^2+, Dy^3+ phosphors were initially prepared by the solid reaction method. Three kinds of glass frits were prepared to match the SrAl2O4: Eu^2+, Dy^3+ phosphors. Effects of the compositions of the glass frits, the ratios of the phosphors to the frits us well us the firing temperature and firing times on the properties of the samples were discussed. XRD analysis indicated the samples exhibited the typical diffraction peaks of SrAlwO4: Eu^2+, Dy^3+. The emission spectra of the samples showed broad bands peaking at 510nm.The excitation spectra of the samples showed broad bands ranging from 300 to 480hm. These are believed due to the 5d4f-4f transitions of Eu^2+ in the SrAl2O4: Eu^2+, Dy^3+ phosphors. The afterglow luminescence of the samples excited by a 40W fluorescence lamp for 30min can be observed in the dark for more lOh with the naked eyes. It can find wide applications in many fields.  相似文献   

7.
Sr2CeO4既是一种有重要应用价值的新型蓝色荧光体,又是一种适合稀土掺杂的发光基质。近年来人们对稀土掺杂的Sr2CeO4的荧光性能进行了研究。本文结合作者的工作,分析了Sr2CeO4的结构特点和光谱特性:综述了Eu^3+,Sm^3+,Dy^3+等稀土离子掺杂Sr2CeO4的发光性能的研究现状,并对今后的研究工作提出了一些设想。  相似文献   

8.
Eu^2+在Sr4Al14O25基磷光体中能量传递行为的研究   总被引:2,自引:0,他引:2  
合成了3种不同Eu掺杂量的Sr4Al14O25,Dy^3 发光粉体,发现当Eu掺杂量低于0.012mol时,发射光谱中存在2个主发射峰,分别位于407nm和494nm。随着Eu掺杂浓度增加,407nm发射峰逐渐消失,而494nm主发射峰增强。结合Sr4Al14O25,晶体结构和激发.发射光谱,建立了2种Eu发光中心之间的能量传递模型,对实验现象进行了合理的解释。余辉衰减曲线测试结果表明,3种磷光体试样均具有长余辉性能,尤其Sr4Al14O25:Eu0.0l2,Dy0.024试样,其余辉时间在人眼可视亮度水平可持续20h以上。  相似文献   

9.
CaAl2O4:Eu^2+,Nd^3+纳米粉体的合成与表征   总被引:1,自引:0,他引:1  
采用溶胶一凝胶法制备了CaAl2O4:Eu^2+,Nd^3+纳米粉体发光材料。样品的XRD和SEM分析结果表明:800℃已形成CaAl2O4晶相;样品颗粒尺寸随灼烧温度升高而增加,平均粒径约为20nm~40nm。光谱分析表明:样品的激发光谱为240nm~400nm的宽带谱,在256.6nm和330.6nm处有激发峰。发光光谱是386nm~500nm的宽带谱,峰值位于440nm,与CaAl2O4:Eu^2+,Nd^3+粗晶材料相比,光谱发生了“蓝移”现象。样品的热释光峰值位于206℃,与粗晶材料相比,峰值向高温移动了96℃,热释发光峰曲线形状也变宽。样品的发光衰减是由初始的快衰减和随后的慢衰减构成,余辉时间为5h。  相似文献   

10.
Nano-sized SrAl2O4:Eu^2+,Dy^3+ phosphors with good monodispersity and narrow size distribution were synthesized by the coupling of water-in-oil (W/O) microemulsion with coprecipitation method. The phase composition, morphology, crystallinity, excitation spectra, emission spectra, and afterglow decay of SrAl2O4:Eu^2+,Dy^3+ nanophosphors were measured. It was found that the amount of surfactant that was used had an important effect on the shape and average size of the phosphor particles. SrAl204 phase of the phosphors showed an increase with the increase in calcination temperature. When the calcination temperature reached 1150℃, the fine crystal of SrAl2O4 was formed and the long afterglow luminescence could be obviously observed. In comparison with the samples prepared by the high-temperature solid-state method, the calcination temperature showed an obvious decrease and a dear blue shift occurred in the excitation and emission spectra of the sample. The afterglow time could be more than 8 h.  相似文献   

11.
采用高温固相反应按化学式Sr4-xBaxAl14O25: Eu2+, Dy3+(x=0, 0.8, 1.6, 2.4, 3.2, 4) 配比原料,合成长余辉发光材料。X射线衍射分析表明,当x=0.8时,产物物相为单斜结构SrAl2O4和磁铅矿结构SrAl12O19共存;当x>1.6时,产物主相转变为BaAl2O4六角结构。对所得样品采用360 nm光照,发射光谱表明,样品发光是以Eu2+为发光中心,由Eu2+电子4f65d-4f7跃迁所致,并且随着Ba掺入量的增加,样品发射光谱峰位产生移动,这是由于Sr2+取代产物中Ba2+位置后,导致晶格收缩,影响Eu2+的5d能级劈裂,从而影响电子4f65d-4f7跃迁。余辉光谱显示x>1.6时,产物的余辉发光是以BaAl2O4基质中Eu2+为发光中心。余辉衰减检测和热释光谱分析发现不同掺Ba量的样品余辉衰减快慢不同,是由于其中存在的陷阱能级深度不同,且陷阱能级越深,其余辉时间越长  相似文献   

12.
The roles of different point defects in persistent luminescence of SrAl2O4:Eu,Dy phosphors were investigated. The research results showed that Dyer plays an important role in the persistent luminescence of SrA1EO4:Eu, Dy phosphors. It can serve as the electron trap of suitable depth for persistent luminescence. V~ does not serve as the electron trap of suitable depth, but its existence can increase the depth of electron traps. There is interaction between the Dy^3+( DySr ) and the Eu^2+(Eu^x Sr ), and only if the distance between the Dy^3+(DySr) and the Eu^2+ (Eu^x Sr) is close enough, the Dyer can work as an effective electron trap. The point defect of V" Sr can be hole trap, but the change of its density in crystal matrix does not arouse the obvious change of persistent luminescence.  相似文献   

13.
稀土离子RE(RE=Pr,Nb,Eu)在Sr2CeO4基质中的发光性质   总被引:2,自引:0,他引:2  
高峰  陈震 《稀有金属快报》2005,24(12):23-26
通过燃烧法合成了Sr2CeO4:RE材料,研究了Sr2CeO4材料的结晶过程和发光性质及Pr^3+,Nd^3+和Eu^3+稀土离子在Sr2CeO4基质中的发光性能。实验通过燃烧法制得的前驱体在1200℃焙烧2h可得均一的Sr2CeO4相,较传统方法的合成时间大为降低。稀土离子Pr^3+,Nd^3+和Eu^3+的在基质中的少量掺杂(0.02%)均可使Sr2CeO4在475nm左右的特征发射谱峰明显变宽增强,且Eu^3+离子的掺杂可使材料在510nm,540nm,610nm左右产生多个明显的稀土离子的特征发射峰。实验合成的发光材料具有良好的发光性能,证明Sr2CeO4材料可作为一种优良的发光材料的基质使用,为寻找新型的发光材料提供了一条新的途径。  相似文献   

14.
采用高温固相法合成了长余辉发光材料Sr3-xCaxAl2O6:Eu2+, Dy3+(x = 0, 1, 2, 3),研究了样品的结构、光致发光、余辉发光和热释发光性能。结果表明:所制备的样品具有相似的结构,均为立方结构的Sr3-xCaxAl2O6。Sr/Ca比例的变化并没有引起基质结构的相变,但对样品的发光性能产生了显著影响;样品的余辉衰减曲线符合双指数衰减,但不同样品的初始强度和衰减快慢不同;通过调节锶钙比的方法,可以有效调控样品光致发光的颜色和余辉衰减特性。此外,测试样品的热释光曲线发现当样品中有两种不同深度的陷阱能级时,样品的余辉强度明显减弱,这可能与电子在不同的陷阱能级的转移有关。  相似文献   

15.
新型蓝色长余辉发光材料Sr2Al6O11:Eu^2+,Er^3+的微波合成   总被引:2,自引:0,他引:2  
在微波场作用下,首次合成了蓝色长余辉发光材料Sr2Al6O11: Eu2 , Er3 ,利用XRD对其进行晶相分析,用荧光光度计测其激发光谱和发射光谱及余辉衰减曲线,利用热释光剂量仪测定其热释光谱.结果表明:该产品为正交晶系,Pnnm空间群,a= 2.191 827 nm,b=0.840 857 nm,c=0.488 175 nm,该产品激发和发射谱均为宽带谱,在270和340 nm处有2个主激发峰,主发射峰位于460 nm,Sr2Al6O11: Eu2 ,Er3 的发光余辉可持续14 h以上,Sr2Al6O11: Eu2 ,Er3 中存在2个热释峰,一个位于49.1 ℃,另一个位于140 ℃左右.2个陷阱能级分别为0.585 eV和0.806 eV.  相似文献   

16.
采用固相法和水热法制备了BaAl2B2O7:Eu^3+系列发光体,研究了制备方法对其光谱特性的影响、助熔剂对发光强度和微观形貌的影响、激活剂浓度对发射强度的影响。研究表明;固相法制备的发光体Eu^3+存在621nm的^5D0→^7F2强发射和772nm的^5Do→^7F5.6弱发射,通过对多种助熔剂优选NaF为最佳的助熔剂,掺杂NaF的发光体仅在772nm的发射大幅度增强,说明助熔剂对发射光谱的特定波长有突出的增强作用:当掺杂Eu^3+浓度较低时和水热法制备的荧光体在455nm存在Eu^2+的4f^65d^1→^8S7/2强发射;此外还研究了BaAl2B2O7:Eu^3+中Eu^2+→Eu^3+的能量传递。  相似文献   

17.
以NaOH,Y(NO3)3·6H2O和Eu(NO3)3.6H2O为前驱体,通过添加络合剂PEG-2000,采用水热法,成功地合成了Y2O3:Eu^3+纳米棒和纳米管,并采用先进的测试手段对其结构和性能进行了表征与测试。探讨了Y2O3:Eu^3+纳米棒和纳米管的生长机制,同时研究了Y2O3:Eu^3+纳米晶的光致发光性能。研究结果表明,水热温度、反应时间、NaOH的添加量和PEG-2000对产物形貌有着非常重要的影响,所制备的材料具有Eu^3+的特征红光发射,并在Eu^3+的掺杂量为5%(摩尔分数)时样品发光最好。  相似文献   

18.
高温固相法制备了在CaO-B2O3-CaCl2(CBC)基质中单双掺杂Eu^3+,Sm^3+,Sm^3+/Eu^3+的高光效发光材料。首次研究CBC对发光体光谱行为的影响;助熔剂对CBC:Eu^2+IR光谱的影响等。结果表明:发光体与基质的激发和发射光谱存在同位发射效应。由于基质能带隙中能级和标准还原电位不同,非还原条件掺杂三价Eu^3+,Sm^3+得到Eu^2+,Sm^3+的发射。在CBC:Sm^3+/Eu^2+中Sm^3+是Eu^2+的高效敏化剂,存在激活剂与CBC的能量传递及Sm^3+→Eu^2+的共振能量传递。助熔剂LiCl对大部分低频区IR谱的T%有增强作用。  相似文献   

19.
以SrCO3、CaCO3、4MgCO3·Mg(OH)2·5H2O、SiO2等为原料,用高温固相烧结法合成了发光性能良好的Sr2-xCaxMgSi2O7:Eu2+,Dy3+长余辉发光材料,借助于X射线衍射和荧光光谱等研究手段对其进行了分析和表征,探讨了Ca2+取代Sr2+和稀土离子的掺入量及固相反应温度、时间对其发光性能的影响。结果表明:Sr2-xCaxMgSi2O7:Eu2+,Dy3+长余辉发光材料的较佳烧成温度为1250~1300℃,烧成时间为3h左右;其物相单一,只含有与四方晶系的Sr2MgSi2O7晶相相同的固溶体Sr2-xCaxMgSi2O7相;紫外光和日光均可使其激发发光,随着钙取代锶量的增大,其发射峰逐渐向长波方向移动,发光颜色由蓝绿色变成黄色,但其发光性能变差。钙的取代量为0.5mol以下样品的发光性能良好,余辉时间可达13h以上。  相似文献   

20.
Strontium aluminate long persistence phos phors are synthesized by combustion method. By control- ling the raw material ratio (Sr/Al), the effects of phase composition on subsequent spectroscopic properties of phosphors are studied. Results show that the phase com-position changes from strontium-rich phase to aluminum- rich phase with the decrease of Sr/AI: when the rate of Al/Sr changes from 3:1 to 1:1, the main crystal phase of samples is Sr3Al206, and it exhibits the characteristic fluorescence of Eu^3+ in the lattice of Sr3Al206; when the rate of Al/Sr is between 1:2 and 2:7, phase composition is the mixture of SrAl204 and SrAl4OT, and it emits the characteristic fluorescence of Eu^2+ in SrAl204 but not in SrAl4OT; when Al/Sr decreases to 1:4 or even 1:12, the main crystal phase of samples transform into SrAl12019, and the characteristic emission peak is about 470 nm, which corresponds to the characteristic emission of Eu2+ in SrAl12019. At the end of the article, the influence laws of two different synthesis methods on phase composition of samples between high-temperature solid method and combustion method are compared. Compared with the high-temperature solid method, the rule of influence is similar, but the mole ratio of Al/Sr in products is always higher than the initial ratio of the raw material, and com-pounds like Sr4Al14025 are not obtained by combustion method.  相似文献   

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