摘要
采用Gd_2O_3,Yb_2O_3,Er_2O_3,HNO_3,CO(NH_2)_2和C_(12)H_(25)SO_4Na为实验原料,通过水热法合成了纳米Gd_2O_3:Yb^(3+),Er^(3+)上转换发光粉体。通过X射线衍射(XRD)、差示扫描量热-热重分析(DSC-TGA)、傅里叶变换红外光谱(FT-IR)、透射电子显微镜(TEM)和上转换发射光谱(UCL)等对样品进行表征。研究结果表明:CO(NH_2)_2与Gd^(3+)离子的摩尔比m影响前驱体的组成,当m=4时,前驱体是由晶态的Gd_2(CO_3)_3·xH_2O构成。该前驱体在空气气氛下800℃煅烧2h可获得单相的Gd_2O_3纳米粉体,粉体呈近球状,平均粒径约为30~40nm。上转换发光光谱表明,在980nm波长红外光激发下,Gd_2O_3:Yb^(3+),Er^(3+)的主发射峰位于664nm波长处,呈红光发射,对应于Er^(3+)的~4F_(9/2)→~4I_(15/2)跃迁。在波长为539nm和562nm附近呈现绿光发射,分别对应于Er^(3+)的~2H_(11/2)→~4I_(15/2)和~4S_(3/2)→~4I_(15/2)跃迁。Er^(3+)的猝灭浓度为1%。800℃煅烧合成的Gd_2O_3:Yb^(3+),Er^(3+)纳米粉体的上转换发光机制为双光子模型,而1 200℃煅烧合成的Gd_2O_3:Yb^(3+),Er^(3+)纳米粉体的上转换发光机制则为三光子模型。
Gd2O3：Yb3＋,Er3＋ nanophosphors were synthesized via a hydrot hermal synthesis method with the starting materials of Gd2O3,Yb2O3,Er2O3,HNO3,CO（NH 2）2and C12H25SO4Na. The samples were characterized by X-ray diffraction （XRD）,differential scannin g calorimetry thermogravimetric analysis （DSC-TGA）,fourier transform infrared spectrosc opy （FT-IR）, transmission electron microscopy （TEM） and up-conversion luminescence （UCL） spectra.The results show that the molar ratio of Gd3＋ has a great influence o n the phase structure of the precursor.The precursor is composed of Gd2（CO3）3·xH2O when th e molar ratio of Gd3＋ is 4,which can be transformed into near-spherical Gd2O3powder with the average size of 30-40nm by calcini ng at 800℃ for 2h in air.Under 980nm infrared laser excitation,the strongest emission peak f or the Gd2O3：Yb,Er nanophosphors is located at 664nm,which corresponds to t he F9/2→I15/2 transition of Er ions.Moreover,the Gd2O3：Yb,Er nanophosphors also show green e mission peaks at 539nm and 562nm,which are attributed to the transitions of H11/2→I15/2 and S3/2→I15/2 of Er ions,respectively.The quen ching concentration of Er ions is 1%.The Gd2O3：Yb,Er nanophosphors show two-photo model emission mechanism at 800℃ .When the temperature increases to 1200℃,the emission mechanism chan ges into three-photo model.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2017年第11期1233-1239,共7页
Journal of Optoelectronics·Laser
基金
国家级大学生创新创业训练计划项目(201710148000031)
辽宁省自然科学基金(20170540582)资助项目
关键词
Gd2O3纳米粉体
水热合成
上转换发光
Gd2 O3
nanophosphor
hydrothermal synthesis
up-conversion luminescence
