Li^+共掺杂对掺Er^(3+):TiO_2粉末上转换发光特性的影响  

Effect of Li^+ Codoping on the Upconversion Emissions of Er^(3+)-Doped TiO_2

作　　者：曹保胜[1] 冯志庆[1] 何洋洋[2] 李慧[3] 董斌[1] 王兴军[4] 

机构地区：[1]大连民族学院理学院,辽宁大连116600 [2]杜伊斯堡埃森大学物理学院,德国杜伊斯堡47057 [3]大连民族学院生命科学学院,辽宁大连116600 [4]北京大学区域光纤通信网与新型光通信系统国家重点实验室,北京100871

出　　处：《光学学报》2010年第7期1861-1865,共5页Acta Optica Sinica

基　　金：国家自然科学基金(10804015);辽宁省科技厅博士启动基金(20071095);辽宁省教育厅高校科研项目(2008123);大连市科技计划项目(2008J23JH022)资助课题

摘　　要：采用溶胶-凝胶法制备摩尔分数为x(Er3+)=0.1%Er3+,x(Li+)=0~2%Li+共掺杂TiO2粉末。800℃烧结Li+共掺杂促进掺Er3+:TiO2由锐钛矿向金红石相转变,900℃和1000℃烧结Er3+-Li+:TiO2均为单一金红石相。976 nm激光激发下Er3+-Li+:TiO2均获得中心波长为526 nm和550 nm的绿色和663 nm的红色上转换发光,绿色和红色上转换发光均为双光子吸收过程。随着Li+共掺杂浓度逐渐增大,800℃烧结Er3+-Li+:TiO2上转换发光强度逐渐减小,900℃烧结发光强度先增加后减小,1000℃烧结发光强度显著增强。不同烧结温度下Li+共掺杂对Er3+所处晶体场对称性的改变导致上转换发光强度随Li+共掺杂浓度增加出现不同的变化规律。结果表明,Li+共掺杂可有效提高Er3+:TiO2上转换发光强度。The TiO2 powders codoped by mole fraction x（Er3＋）=0.1% Er3＋ and x（Li＋）=0~2% Li＋ are prepared by the sol-gel method.The TiO2 phase transition from anatase to rutile is accelerated by Li＋ codoping at the sintering temperature of 800 ℃,while only rutile phase existes at 900 ℃ and 1000 ℃.The green and red upconversion emissions centering at about 526,550 and 663 nm are detected by using a 976 nm semiconductor laser diode excitation.The two-photon Absorption upconversion process is responsible for the green and red upconversion emissions.With the increase of the Li＋ codoping concentration,the upconversion emissions intensities of Er3＋-Li＋：TiO2 sintered at 800 ℃ decreases,and that increases firstly and then decreases at 900 ℃,while the emission intensity increases significantly at 1000 ℃.The changes of crystal-field symmetry of Er3＋ caused by Li＋ codoping at different sintering temperature result in the variation of upconversion emission intensities of Er3＋-Li＋：TiO2.It is found that Li＋ codoping can efficiently enhance the upconversion emission intensities of Er3＋：TiO2.

关 键 词：光学材料 Er3+:TiO2 Li+共掺杂 溶胶-凝胶法 上转换发光 晶体场对称性 

分 类 号：TQ134[化学工程—无机化工]