CaSi_2O_2N_2：Ce^(3＋)/Eu^(2＋)荧光粉的发光性能研究  

Luminescence properties of CaSi_2O_2N_2:Ce^(3+)/Eu^(2+) phosphors

作　　者：罗思远[1] 李绪诚[1] 崔瑞瑞[1] 邓朝勇[1] 

机构地区：[1]贵州大学大数据与信息工程学院电子科学系,贵州省电子功能复合材料特色重点实验室,贵州贵阳550025

出　　处：《光电子．激光》2015年第5期899-904,共6页Journal of Optoelectronics·Laser

基　　金：贵州省科技计划(2012-3005,2011-2016,2010-4005,2009-15,2010-2134);贵阳市科技计划(2012101-2-4)资助项目

摘　　要：采用高温固相反应法制备了CaSi2O2N2:Ce3+/Eu2+荧光粉,研究了分别掺杂Ce3+、Eu2+及Ce3+/Eu2+共掺杂时荧光粉的发光特性。CaSi2O2N2:Ce3+在333nm激发下得到宽波段的发射谱,发射峰位于395nm,随着Ce3+浓度的增大,发射波长出现明显的红移,猝灭浓度为1 mol%。CaSi2O2N2:Eu2+在397nm激发下得到峰值位于540nm处的宽波段发射谱,猝灭浓度为1 mol%。对于Ca0.99-2 xSi2O2N2:xCe3+,xLi+,0.01Eu2+荧光粉,在333nm激发下,位于395nm处的发射峰十分微弱,在540nm处有宽带发射,随着Ce3+浓度增大,位于540nm处的Eu2+的特征发射显著增强。对于Ca0.98-ySi2O2N2:0.01Ce3+,0.01Li+,yEu2+荧光粉,在激发光波长为333nm,Eu2+浓度较低时,可以观察到两个发射带,峰值分别位于395nm及540nm,随着Eu2+浓度增加,位于395nm的发射强度一直减小,而540nm处的发射强度先增加后减小,猝灭浓度为0.4mol%。证实了Ce3+,Eu2+之间发生了有效的能量传递。计算出Ce3+、Eu2+之间能量传递的效率ηT,在Eu2+浓度为1 mol%时ηT趋于饱和,达到97.7%。通过计算,得到Ce3+与Eu2+之间的能量传递方式为电偶极-电偶极相互作用。CaSi2 02 N2 ： Ce3＋ method. Photol /Eu2＋ phosphors were successfully synthesized via the solid-state reaction properties of Ce3＋ -doped, Eu2＋ -doped and Cea＋/Eu2＋ codoped samples are investigated. CaSi2 02 Ne ..Cea＋ phosphors show a broad band centered at 395 nm under 333 nm excita- tion. Red-shift occurs as the concentration of Cea＋ increases. The molar quenching concentration of Cea＋ is approximately 1 %. CaSi2 02 N2 ： Eu2＋ phosphors emit a single, intense, and broad emission band cen- tered at 540 nm when excited at 397 nm. The molar quenching concentration of Eu2＋ is approximately 1%. When excited at 333 nm,the codoped samples Ca0.99-2xSi202N2 ：xCe3＋ ,xLi＋ ,0. 01Euz＋ emit two broad bands centered at 395 nm and 540 nm,respectively. The emission of Eue＋ is significantly en- hanced by the increase of Ce3＋. When Ca0.98-sSi2 02 N2：0. 0iCea＋ , 0. 01Li＋ ,yEu2＋ phosphors are ex- cited at 333 nm,two broad bands with peaks at 395 and 540 nm are observed. The former band （at 395 nm） is weakened when increasing Eu2＋ content. However,the band at 540 nm reaches the maximum in- tensity for y = 0. 004. These suggest effective energy transfer mechanism from Ce3＋ to Eu2＋ taking place in the CaSi2 02 N2 sample. The efficiency of energy transfer between Cea＋ and Eu2＋ is calculated, and saturation value occurs when the concentration of Eu2＋ increases to 1%. The resonance-type energy transfer between Cea＋ and Eu2＋ is dipole-dipole interaction mechanism.

关 键 词：CaSi2O2N2 白光发光二极管(WLED) 荧光粉 稀土 能量传递 

分 类 号：O482[理学—固体物理]