量子点由于特殊的结构特点,显示出良好的光电性能,受到广泛的应用.然而其具有的生物毒性违背了环境友好型可持续发展战略,日益受到人们的关注.ZnS作为一种低毒低污染的半导体材料,是目前的研究热点.但单纯的ZnS量子点带隙较宽,电子跃迁所需吸收的光子较多,故难以产生稳定且性能良好的发光.通过掺杂Cu2+后,ZnS量子点的发光效率提高,光电性能更为稳定,且保持低毒低污染的优势.文章中采用热注入法制备出ZnS量子点并掺杂Cu2+,通过X射线衍射图谱(XRD)、透射电子显微镜(TEM)以及荧光光谱(PL)对上述样品进行表征.ZnS量子点呈颗粒状均匀分布,具有六方纤锌矿结构;其发光强度较弱,在约470 nm和540 nm左右显示发光峰,分别对应本征峰和表面缺陷峰.掺杂Cu2+后量子点的发光性能得到了显著地提高.此外进一步研究了S含量、Cu2+掺杂量和加入硫源((NH4)2S)后的反应时间对ZnS∶Cu量子点发光性能的影响.%Due to the unique structure of quantum dots,quantum dots show good photoelectric properties.With the concept of sustainable development spreading widely and deeply in people's opinion,the toxicity of quantum dots has attracted more and more attentions.As a low toxicity and low pollution semiconductor material,ZnS is a hot research topic.However,due to its wide band gap,more photons need to be absorbed during the electron transition,so it is difficult to produce stable and good luminescence performance.After doping Cu2+,the luminescence efficiency of ZnS quantum dots is improved,the photoelectric properties are more stable,and the advantages of low toxicity and low pollution are maintained.In this paper,ZnS quantum dots and Cu2+ doped ZnS quantum dots were prepared by hot injection method,and the XRD characterization,TEM characterization and fluorescence spectra analysis were carried out.The luminescence intensity of ZnS quantum dots with hexagonal wurtzite structure is weak,and has two emission peaks at 470 nm 540 nm,which correspond to the intrinsic luminescence peak and the surface defect peak.The luminescent properties of the quantum dots doped with Cu2+ were remarkably improved.Therefore,we investigated the effect of S content,Cu2+ content and the reaction time after the addition of sulfur ((NH4)2S) on the luminescent properties of ZnS∶Cu quantum dots.
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