采用高温固相反应合成了SrAl2O4-yNy∶Eu2+,Dy3+系列长余辉荧光粉,并研究了SrAl2O3.75N0.25∶Eu2+,Dy3+体系的晶体结构、光谱特性、余辉衰减曲线及热释发光曲线.X射线衍射分析结果表明,SrAl2O3.75N0.25:Eu2+荧光材料属六方晶系,P6322空间群,晶胞参数a=b=5.14,c=8.462,γ=120°.荧光光谱测试结果表明,SrAl2 O3.75N0.25∶Eu2+的激发光谱和发射光谱均为宽带谱,激发光谱位于283 nm ～450 nm,发射光谱的峰值位于487 nm,属于Eu2的4f65d1→4f7跃迁发射.Eu2+的掺杂量并不改变SrAl2O3.75N0.25∶Eu2+发射光谱的形状和峰值位置,但对相对发光强度有较大影响,Eu2+的摩尔浓度为2％时相对发光强度最高.余辉衰减曲线表明,Sr0.97 Al2O3.75N0.25∶Eu0.02,Dy0.01的余辉衰减符合指数衰减规律,由初始的快衰减和之后的慢衰减两个过程组成.通过热释发光曲线对荧光材料中的陷阱能级进行计算,得出Sr0.97 Al2 O3.75 N0.02∶Eu0.02,Dy0.01的能级陷阱为0.42 V,掺Dy3+有利于提高该荧光材料的初始发光亮度和余辉时间.
The long afterglow phosphors SrAl2O4-yNy∶ Eu2+,Dy3+ were synthesized by the conventional solid state reaction method.The crystal structure,luminescence properties,afterglow decay curves and thermoluminescence of SrAl2 O3.75 N0.25∶ Eu2+,Dy3+ phosphor were studied.The XRD results showed that the crystal structure of SrAl2O4-yNy∶ Eu2+,Dy3+ belong to hexagonal system,space group P6322,lattice parameters a =.b =5.14,c =8.462,γ =120°.A broad excitation band at 283 ～450 nm was observed for SrAl2O 4-yNy∶Eu2+,Dy3+,and the emission band at 487 nm resulting from the 4f65d1→4f7 transition of Eu2+ ions.The emission spectra don' t change with Eu2+ concentration.The emission intensity of SrAl2 O3.75 N0.25 ∶Eu2+,Dy3+ phosphor was enhanced with the increase of Eu2+ concentration and the highest emission was obtained at 0.02 mol Eu2 + concentration.The afterglow decay of Sr0.97 Al2 O3.75 N0.25:Eu0.02,Dy0.01 was accorded with the exponential decay rule,which was composed of the original fast decay and the late slow decay.The thermoluminescence results showed that energy trap of phosphor Sr0.97 Al2 O3.75 N0.25 ∶ Eu0.02,Dy0.01 was 0.42 eV,the co-doption of Dy3 + can help to achieve high brightness and long afterglow.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%