Ce^(3+)掺杂对NaYF_(4)∶Yb^(3+),Tm^(3+)纳米粒子上转换发光性能的影响及其荧光温度特性应用  

Effect of Ce^(3+) Doping on Upconversion Luminescence of NaYF_(4)∶Yb^(3+),Tm^(3+) Nanoparticles and Application of Fluorescence Temperature Characteristics

作　　者：蒙铭周 张瑞[1] 法信蒙 杨江华 欧俊[1] MENG Ming-zhou;ZHANG Rui;FA Xin-meng;YANG Jiang-hua;OU Jun(Guangxi Key Laboratory of Nonferrous Metals and Special Materials Processing, College of Material Science and Engineering, Guilin University of Technology, Guilin 541004, China)

机构地区：[1]桂林理工大学材料科学与工程学院,广西有色金属及特色材料加工重点实验室,广西桂林541004

出　　处：《发光学报》2021年第11期1763-1773,共11页Chinese Journal of Luminescence

基　　金：广西重点科研项目(2016GXNSFDA380026)资助。

摘　　要：采用溶剂热法制备了一系列不同Ce^(3+)含量的Yb^(3+)/Tm^(3+)/Ce^(3+)共掺NaYF_(4)纳米粒子。样品在980 nm激光激发下,可以观察到强烈的上转换蓝色荧光。探究了不同Ce^(3+)含量对发光强度的影响,发现在Ce^(3+)含量从0%增加到0.5%的过程中,紫外到可见的上转换发光随着Ce^(3+)浓度的增加先增强后减弱,在0.2%时荧光达到最强,比不掺Ce^(3+)时荧光增强高达5倍左右,其中475 nm的蓝光更是增强了6倍。此外,对其机理进行了深入细致的探究,一方面,掺杂Ce^(3+)后,Tm^(3+)中的(^(3)F_(3),^(3)H_(4))与Ce^(3+)中的(^(2)F_(7/2),^(2)F_(5/2))发生交叉弛豫,有效地防止了电子跃迁回到基态,以致整体荧光明显增强;另一方面,当掺入Ce^(3+)后,形成的(Yb^(3+)-Yb^(3+)-Ce^(3+))Trimers把能量传递给^(1)G_(4)能级,发出475 nm的蓝光,导致蓝光很强。将其应用于荧光强度比测温,绝对灵敏度高达0.0350 K^(-1)。A series of Yb^(3+)/Tm^(3+)/Ce^(3+) co-doped NaYF_(4) nanoparticles with different Ce^(3+) contents were produced by solvothermal method.Strong upconversion blue fluorescence can be observed under 980 nm laser excitation.The influence of different Ce^(3+) content on the luminescence intensity was investigated.It was found that the upconversion luminescence from UV to visible enhanced firstly and then weakened with the increase of Ce^(3+) concentration when the mole fraction of Ce^(3+) increased from 0%to 0.5%.The fluorescence intensity reached the maximum at 0.2%,which was about 5 times stronger than that without Ce^(3+) doping,and the blue light at 475 nm was enhanced by 6 times.In addition,the mechanism was explored in detail.On the one hand,the cross relaxation between(^(3)F_(3),^(3)H_(4))in Tm^(3+) and(^(2)F_(7/2),^(2)F_(5/2))in Ce^(3+) occured after doping Ce^(3+),which effectively prevented the electron transition from going back to the ground state,resulting in the overall fluorescence enhancement.On the other hand,the(Yb^(3+)-Yb^(3+)-Ce^(3+))Trimers formed by doping Ce^(3+) transfered energy to 1G4 level and emitted 475 nm blue light,which led to strong blue light.When it was applied to the fluorescence intensity ratio thermometry measurement,the absolute sensitivity was as high as 0.0350 K^(-1).

关 键 词：Ce^(3+)掺杂 上转换发光 强蓝光 (Yb^(3+)-Yb^(3+)-Ce^(3+))Trimers 荧光强度比测温 

分 类 号：O482.31[理学—固体物理]