CdTe,核-壳型CdTe/CdS及CdTe/ZnS量子点的合成及表征(英文)  

CdTe,Core-shell CdTe/CdS and CdTe/ZnS Quantum Dots:Their Synthesis and Characterization

作　　者：张纪梅[1] 许世超[1,2] 宋秀云[1] 代昭[1] 孙波[3] 姚翠翠[1] 

机构地区：[1]天津工业大学材料科学与化学工程学院,教育部中空纤维膜材料及膜过程重点实验室,天津300160 [2]天津工业大学生物与纺织材料研究所,天津300160 [3]南开大学化学学院,天津300071

出　　处：《光子学报》2009年第4期905-910,共6页Acta Photonica Sinica

基　　金：Supported by Tianjin Natural Science Foundation(07JCYBJC15900)

摘　　要：在水相中制备了半导体CdTe纳米晶,核-壳型CdTe/CdS和CdTe/ZnS纳米晶(即量子点;QDs).利用扫描隧道显微镜(STM)和荧光光谱(FS)对合成的纳米晶量子点进行了研究,并且根据FS的数据进行了量子效率的计算.STM的结果表明合成的量子点直径约为3nm并且分布良好.为了提高量子效率,对Cd2+浓度和Cd2+∶S2-比例等反应条件进行了研究,结果表明随着回流时间的增加,核-壳型量子点CdTe/CdS的量子效率总体上呈下降趋势.CdTe/CdS在pH8.5,Cd2+∶S2-=10∶1(摩尔比)时可获得80.0%的最大量子效率.同时制备了核-壳型量子点CdTe/ZnS,其最大发射波长由551nm(CdTe)红移到635nm(CdTe/ZnS)表明量子点的尺寸在增长,但是量子效率下降到14.4%.当前研究的量子点可适用于生物标记,生物成像,以及基于共振能量转移的生物传感研究.Semiconductor CdTe, core-shell CdTe/CdS and CdTe/ZnS nanocrystals（quantum dots; QDs） were prepared in aqueous phase. Investigations of the prepared nanocrystals were performed via scanning tunneling microscope （STM） and fluorescence spectrum （FS）, and quantum yields（QYs） was calculated based on the resulting data from FS. Particle size of well dispersed CdTe was evaluated to he ca 3 nm via STM. Some reaction conditions were investigated and discussed to enhance QYs of CdTe/CdS core-shell QDs, such as dependence of Cd^2＋ concentration, and effect of Cd^2＋ S^2- etc. Among all of those methods, QYs of core-shell CdTe/CdS is generally degressive with refluxing time elapsing. The best QYs of ca 80.0% can be achieved when pH was set at 8.5, Cd^2＋ ： S^2- =10.1（mol ratio）. Moreover, CdTe/ZnS core-shell QDs was prepared, and results indicated a red-shift from 551 nm to 635 nm comparing with CdTe core, which suggested the growth of QDs size, however, QYs of CdTe/ZnS decreased to 14.4%. QDs currently discussed in this research are easily synthesized, and they will be useful in applications of biolaheling, imaging, and biosensing based on fluorescence resonance energy transfer（FRET）.

关 键 词：光谱学 合成与表征 CdTe/CdS及CdTe/ZnS核-壳型量子点 量子效率 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]