核/壳结构ZnS:Mn/ZnS量子点光发射增强研究

利用水溶性前驱体材料在水性介质中制备了ZnS:Mn和ZnS:Mn/ZnS核/壳结构量子点(QDs,quantum dots),并用X射线衍射(XRD)、光致发光(PL)对ZnS:Mn和ZnS:Mn/ZnS核/壳结构QDs的结构和发光性能进行研究.ZnS:Mn和ZnS:Mn/ZnS QDs XRD谱与标准谱吻合,根据De...

Photoluminescence enhancement of ZnS:Mn/ZnS core/shell quantum dots

ZnS:Mn and ZnS:Mn/ZnS core/shell quantum dots(QDs) were prepared in the aqueous medium from readily available precursors.The construction and luminescence properties of ZnS:Mn and ZnS:Mn/ZnS core/shell QDs were evaluated by X-ray diffraction(XRD) and photoluminescence(PL) spectra.The powder X-ray diffraction(XRD) measurements show that the ZnS:Mn and ZnS:Mn/ZnS core/shell QDs are β-ZnS structure,and the size of ZnS:Mn/ZnS core/shell QDs increases with adding ZnS shells.ZnS:Mn and ZnS:Mn/ZnS core/shell QDs both have photoluminescence at 586 nm through the 4T1-6A1 transition of Mn ions.Specially,the PL intensity of ZnS:Mn/ZnS core/shell QDs is enhanced with adding ZnS shells,and ZnS shells never lead to blue or red shift in PL spectra.It is because ZnS shells can block some non-radiative recombination routes related to the surface state of the QDs,which will increase the concentration of luminescent center and decrease the non-radiative recombination sites.The luminescence intensity of thioglycolic acid(TAG) modified ZnS:Mn QDs decreases significantly,while that of thioglycolic acid modified ZnS:Mn/ZnS QDs decreases slightly,although the stability and solubility of thioglycolic acid modified ZnS:Mn and ZnS:Mn/ZnS QDs are improved.