四方相LaOF:Eu^(3+)红色纳米荧光粉的水热-烧结法制备及其荧光属性  

Fluorescence characteristics of tetragonal LaOF:Eu^(3+) red nano-phosphors prepared by hydrothermal-sintering method

作　　者：何恩节[1] 郑海荣[1] 高当丽[1] 田宇[1] 雷瑜[1] 屈世显[1] 

机构地区：[1]陕西师范大学物理学与信息技术学院,西安710062

出　　处：《中国科学（G辑）》2010年第1期60-68,共9页

基　　金：国家自然科学基金(批准号:10875076);陕西省自然科学基金(批准号:SJ08-ZT13)资助项目

摘　　要：介绍了一种用水热法合成并通过控制烧结条件获得四方相LaOF:Eu3+纳米颗粒的制备方法.光致激发条件下的荧光光谱研究发现,与所制备样品的最强红色荧光发射相对应的Eu3+最佳掺杂浓度为9.0mol%,室温条件下,绿光或紫光激发下的样品红色荧光强度高于其他晶相的LaOF:Eu3+纳米颗粒及商用红色荧光粉.时域和频域光谱的分析结果表明,具有四方相结构的LaOF:Eu3+中,较低的局域对称性使掺杂Eu3+具有大的辐射跃迁几率,从而增强了掺杂离子的红色荧光发射.关于荧光寿命和反对称比的研究结果支持了上述判断.LaOF：Eu^3＋ nanocrystals with tetragonal crystal srtucture were prepared by using hydrothermal technique followed with proper control of post-sintering conditions. Experimental observations on the laser-induced fluorescence emission of prepared samples indicated that the concentration of doped Eu^3＋ ions was 0.9 mol% for the strongest red fluorescence emission. It was found that the red fluorescence emission from tetergonal LaOF：Eu^3＋ nanocrystals was much stronger than that from the rhombohedral LaOF：Eu^3＋ nanocrystals as well as commercial red phosphors under the excitations of green and ultraviolet light at room temperature. Spectroscopic investigations in the frequency and time domains suggested that the lower local symmetry of Eu^3＋ ions in tetragonal LaOF：Eu^3＋ nanocrystals resulted in bigger radiative transition probability of doped Eu^3＋ ions, which induced the enhancement of red fluorescence emission as observed experimentally. Studies on the fluorescence lifetime and inversion symmetry ratio furthersupported the suggestion.

关 键 词：水热-烧结法 晶体结构 局域对称性 辐射跃迁几率 

分 类 号：TB383.1[一般工业技术—材料科学与工程]