Xie Hai-Yan, Liang Jian-Gong, Liu Yi, Zhang Zhi-Ling, Pang Dai-Wen, He Zhi-Ke, Lu Zhe-Xue, Huang Wei-Hua
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China.
J Nanosci Nanotechnol. 2005 Jun;5(6):880-6. doi: 10.1166/jnn.2005.119.
A convenient route for the synthesis of high-quality overcoated II-VI quantum dots (QDs) is reported in this paper. Simple salts, such as Cd(Ac)2 and Zn(Ac)2 were used to replace organometallics, whose disadvantage is obvious. Size-tunable core/shell structured QDs (CdSe/ZnS, CdSe/CdS, etc.) were synthesized. They were of narrow size distribution and had good monodispersivity and photoluminescence (PL) properties. The spectrum was symmetrical and sharp-pointed (with the full width at half-maximum (fwhm) of about 20-30 nm). The quantum yield (QY) was improved to 60-80% from 20-30% for bare QDs and remained stable at least for 6 months. The primary overcoated QDs were modified with biomacromolecules by a direct mechanical rubbing strategy, which is very simple and fast. The results obtained by UV-vis, PL, atomic force microscopy (AFM), and fluorescence microscopy imaging showed that the modified QDs were of good fluorescent and monodisperse characteristics. They are likely to be used further for biological labels.
