Li^+掺杂对TeO_2:Tm^(3+)/Er^(3+)/Yb^(3+)纳米材料上转换发光的增强作用  

Enhancement of Upconversion Luminescence in TeO_2∶Tm^(3+)/Er^(3+)/Yb^(3+) Nanoparticles by Li^+ Doping

作　　者：王霞[1] 胡辉[1] 白燕[1] 

机构地区：[1]暨南大学化学系,广州510632

出　　处：《无机化学学报》2013年第4期659-664,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21075053)资助项目

摘　　要：采用水热法制备了发白光的Li+掺杂α-TeO2∶Tm3+/Er3+/Yb3+和β-TeO2∶Tm3+/Er3+/Yb3+纳米上转换发光材料。采用X射线衍射、透射电镜和上转换发光光谱对制备的TeO2∶Tm3+/Er3+/Yb3+/Li+纳米材料进行表征,结果显示:Li+的掺入基本不改变纳米材料的晶型和结构;在980 nm近红外光的激发下,纳米材料发射出中心波长476 nm的蓝光,525 nm及545 nm的绿光和659 nm及675nm的红光,分别对应于Tm3+的1G4→3H6能级跃迁,Er3+的2H11/2→4I15/2和4S3/2→4I15/2能级跃迁,Er3+的4F9/2→4I15/2能级跃迁和Tm3+的3F2→3H6能级跃迁;Li+的掺入能够增大白光体系的发光强度,基本不改变纳米材料的白光颜色。此外,探讨了纳米材料的上转换发光机理。α-TeO2：Tm^3＋/Er^3＋/Yb^3＋ and β-TeO2：Tm^3＋/Er^3＋/Yb^3＋ nanoparticles with Li＋ doping had been prepared via a hydrothermal method. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy and upconversion luminescence spectra. The results indicated that the doping of Li ＋ ions does not change the crystal form and structure of the as-prepared nanoparticles basically. The as-prepared nanoparticles showed the blue emission （476 nm）, green emissions （525 nm, 545 nm） and red emissions （659 nm, 667 nm） under 980 nm near-infrared light excitation, respectively, corresponding to energy level transition of 1^G4→3^H6 of Tm^3＋ ions, 2^H11/2 →4^I15/2 and 4^S3/2→4^I15/2 of Er^3＋ ions, 4^F9/2→4^I15/2 of Er^3＋ ions and 3^F2→3^H6 of Tm^3＋ ions. The results also indicated that doping of Li＋ ions can increase the luminous intensity of the white light system, and it does not change the white color of the nanoparticles basically. In addition, the upconversion luminescence mechanism of the nanoparticles was analyzed.

关 键 词：Li+掺杂 上转换 纳米TeO2 水热法 

分 类 号：O482.31[理学—固体物理]