Zhang Kexin, Zhang Rui, Yu Yaxin, Sun Shuqing
Department of chemistry, Tianjin University, Tianjin 300072, China.
J Nanosci Nanotechnol. 2012 Apr;12(4):3011-7. doi: 10.1166/jnn.2012.5833.
In this paper, we report a facile method to synthesize high quality CdS: Eu nanocrystals (NCs) and CdS: Eu/ZnS NCs with strong photoluminescence (PL). The influence of various experimental variables including the concentration of Eu3+ ions, the reaction time and the reaction temperature were investigated systematically. In addition, the PL properties of CdS: Eu NCs exhibited pH sensitive. Under the acid condition, pH value of the CdS: Eu NCs solution played an important role in determining PL emission intensity. However, under the alkaline condition, the obtained CdS: Eu NCs exhibited a tunable PL emission wavelength (from 490 nm to 610 nm) when pH value was adjusted from pH 7 to 10. After coating with ZnS shell, the CdS: Eu/ZnS NCs showed enhanced PL intensity compare with one of the CdS: Eu NCs. The CdS: Eu NCs and CdS: Eu/ZnS NCs were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). In addition, the biocompatibility of these NCs was measured by hemolytic test, which indicated that CdS: Eu/ZnS NCs were more biocompatible than CdS: Eu NCs at the same conditions. It can be expected that CdS: Eu/ZnS NCs are promising biolabeling materials.
在本文中，我们报道了一种简便的方法来合成具有强光致发光（PL）的高质量CdS:Eu纳米晶体（NCs）和CdS:Eu/ZnS NCs。系统地研究了包括Eu3+离子浓度、反应时间和反应温度在内的各种实验变量的影响。此外，CdS:Eu NCs的PL性质表现出对pH敏感。在酸性条件下，CdS:Eu NCs溶液的pH值在决定PL发射强度方面起着重要作用。然而，在碱性条件下，当pH值从pH 7调节到10时，所获得的CdS:Eu NCs表现出可调谐的PL发射波长（从490 nm到610 nm）。包覆ZnS壳层后，CdS:Eu/ZnS NCs的PL强度比CdS:Eu NCs之一增强。通过X射线衍射（XRD）和高分辨率透射电子显微镜（HRTEM）对CdS:Eu NCs和CdS:Eu/ZnS NCs进行了表征。此外，通过溶血试验测量了这些NCs的生物相容性，结果表明在相同条件下CdS:Eu/ZnS NCs比CdS:Eu NCs具有更高的生物相容性。可以预期CdS:Eu/ZnS NCs是有前途的生物标记材料。
