NaYF4：Er3＋，Yb3＋纳米晶的液相合成  

Liquid Preparation of Soluble NaYF_4:Er～(3+),Yb～(3+) Nanocrystals

作　　者：贾若琨[1] 杨珊[1] 李翠霞[1] 闫永楠[1] 白玉白[2] 

机构地区：[1]东北电力大学化学工程学院,吉林132012 [2]吉林大学化学学院,长春130061

出　　处：《化学学报》2008年第21期2439-2444,共6页Acta Chimica Sinica

基　　金：吉林省科技厅(No.20070507);吉林省教育厅(No.2007307);吉林市杰青(No.200709)资助项目

摘　　要：采用丙三醇液相结晶法制备了NaYF4∶Er3+,Yb3+上转换纳米晶,合成步骤被简化.常温下,用980nm的红外激光激发可以观察到很强的绿光、红光发射,用荧光光谱仪记录了该上转换光谱.X射线粉末衍射(XRD)结果表明,该方法制备NaYF4∶Er3+,Yb3+纳米晶属于立方混合六方晶系.研究了纳米晶的上转换发光机理,根据晶体场理论对Er3+的两个上转换能级进行了Stark分裂计算,对两个能级之间的谱线进行了归属,进一步证实了980nm光子激发Er3+离子的上转换机理,一个是连续吸收两个980nm光子的过程(激发态吸收),另一个是吸收980nm光子后,电子转移到亚稳态能级,然后再吸收980nm光子过程(能量转移上转换).The NaYF4：Er3＋,Yb3＋nanocrystals have been prepared by liquid crystallization from glycerol. Red at 660 nm and green at 550 nm upconversion emissions were observed from NaYF4：Er3＋,Yb3＋nanocrystals under 980 nm excitation. The X-ray diffraction patterns confirm the nanocrystals are cubic and hexagonal. The mechanism of nanocrystal upconvertion has been studied. The Stark splits of two excitated states of Er3＋ have been calculated based on theory of crystallization fields. The results confirm the upconverted mechanisms in the NaYF4：Er3＋,Yb3＋ nanocrystals are due to two processes, one is a consecutive absorption of two 980 nm photon process, and the other process is that electrons transfer to substeady states after absorption of 980 nm photons, then absorb 980 nm photons.

关 键 词：NaYF4:Er3+ Yb3+ 上转换 Stark分裂 液相结晶 

分 类 号：O611.3[理学—无机化学]