ZnS:Eu/ZnS核/壳结构量子点自发辐射性能研究  

Performance of spontaneous emission of ZnS:Eu/ZnS core/shell quantum dots

作　　者：张晓松[1,2] 李美成[1] 李岚[2] 黄青松[2] 

机构地区：[1]哈尔滨工业大学材料科学与工程学院,黑龙江哈尔滨150001 [2]天津理工大学材料物理研究所,天津300384

出　　处：《红外与激光工程》2011年第4期705-708,共4页Infrared and Laser Engineering

基　　金：国家自然科学基金(60907021);天津市自然科学基金(11JCYBJC00300);天津市高等学校科技发展基金(20071207)

摘　　要：利用水溶性前驱体材料在水性介质中制备了ZnS:Eu和ZnS:Eu/ZnS核/壳结构量子点,并利用XRD、TEM和PL对ZnS:Eu和ZnS:Eu/ZnS核/壳结构量子点的结构和发光性能进行了研究。ZnS:Eu和ZnS:Eu/ZnS量子点XRD谱显示:ZnS:Eu和ZnS:Eu/ZnS量子点具有β-ZnS结构,且随着ZnS壳层增加,ZnS:Eu/ZnS量子点的粒径增大。在波长395 nm紫外光激发下,ZnS:Eu和ZnS:Eu/ZnS量子点在波长592 nm和615 nm存在两个自发辐射,其源于Eu3+离子的5D0→7F1和5D0→7F2的跃迁。ZnS:Eu/ZnS核/壳结构量子点的自发辐射增强,且发射峰并未发生红移或蓝移,主要由于包覆ZnS层后的表面缺陷得到修饰,阻断了某些与量子点表面缺陷相关的非辐射跃迁通道,增加了发光中心浓度,减少了非辐射跃迁几率。ZnS：Eu and ZnS：Eu/ZnS core/shell quantum dots（QDs） were prepared in the aqueous medium from readily available precursors.The construction and luminescence properties of ZnS：Eu and ZnS：Eu/ZnS core/shell QDs were evaluated by X-ray diffraction（XRD） spectra,TEM and photoluminescence（PL） spectra.The XRD measurement showed the ZnS：Eu and ZnS：Eu/ZnS core/shell QDs are β-ZnS structure,and the size of ZnS：Eu/ZnS core/shell QDs increases with adding ZnS shells.ZnS：Eu and ZnS：Eu/ZnS core/shell QDs all have PL at 592 nm and 615 nm through the 5D0→7F1 and 5D0→7F2 transition,specially,the PL intensity of ZnS：Eu/ZnS core/shell QDs increasing with the adding ZnS shells and ZnS shells never leads to blue and red shift in PL spectra.It is the result that ZnS shells can block some non-radiative recombination routes related to the surface state of the QDs,which increases the concentration of luminescent center and decrease the non-radiative recombination sites.

关 键 词：ZnS:Eu/ZnS ZnS:Eu 核/壳结构 量子点 光致发光 

分 类 号：O472[理学—半导体物理]